Russia is developing a new generation mobile surface-to-air missile system – the S-500 (“Prometey”—Prometheus) designed among other things to intercept hypersonic targets traveling at a speed of up to 7 kilometers per second, enabling it to intercept opposing hypersonic cruise missiles. The mobile system can easily “shoot and scoot” to avoid attacks intended to suppress air defenses. It has a range of up to 600 kilometers and it able to simultaneously intercept up to 10 ballistic and hypersonic targets. A reaction speed is only three to four seconds. The first units may be deployed around Moscow and the country's center area as early as 2020. A naval S-500F version for the upcoming Leader-class destroyer is also supposedly in the works for deployment around 2023–25.

The A-235 Nudol hypersonic targets capable missile defense system is going through tests to replace it predecessor-A-135. In addition to ICBM warfare, the A-235 can be used against satellites and hypersonic cruise missiles. With the estimated velocity of 10 km per second, a solid-fuel interceptor will probably need no explosive at all. Being mobile, it could be deployed everywhere, including the territory of friendly states. The A-235 will have missiles capable of operating at three different ranges: long-range, based on the 51T6 and capable of destroying targets at distances up to 1,500 km (930 miles); medium-range, an update of the 58R6, designed to hit targets at distances up to 1,000 km (620 miles); and short-range (the 53T6M or 45T6 (based on the 53T6)), with an operating range of 350 km (215 miles).

With defense systems to counter potential PGS systems in place, Russia does not appear to lag behind the United States in hypersonic strike capability. It has already conducted successful tests of the long-range hypersonic Zircon weapon designed to be carried by advanced and modernized warships and submarines. Russia and India are developing together a hypersonic Brahmos II hypersonic cruise missile.

Russia successfully tested its experimental Yu-74 hypersonic glide vehicle carried by an ICBM. US exoatmospheric interceptors can only operate at altitudes above about 100 km, while almost all of the glide portion of a boost-glide weapon’s trajectory will take place at altitudes below 100 km, making intercepts of gliders by existing GBI or SM-3 interceptors essentially impossible.

According to the «A Threat to America's Global Vigilance, Reach, and Power: High-Speed, Maneuvering Weapons» report produced in late 2016 by a blue-ribbon panel of experts for Air Force Studies Board at the National Academies of Science, the US is falling behind in the technology race to develop both defensive and offensive high-speed maneuvering arms.

The ramping up of hypersonic conventional systems in combination with the buildup of missile defense capabilities could negate all previously reached agreements in the area of limiting and reducing strategic existing balance of power. A recent study by the Rand Corp warns that hypersonic missiles, under development by the United States, Russia, and China and designed to circumvent existing ballistic missile and air defense systems through their unique flight profile, could prompt governments worldwide to set their strategic forces on a "hair-trigger state of readiness.” Besides, Washington's ongoing efforts at creating missile defense systems and developing the PGS precision conventional weapon program has a continued destabilizing effect on nuclear disarmament talks.

The US policy to gain unilateral advantage through developing Prompt Global Strike systems appears to have failed. Russia’s defense industry has come up with technological breakthroughs to match the US effort. Moscow has effective means to counter the US potential PGS systems along with the capability to deliver prompt conventional strikes, making Washington think twice before attacking it. In theory, the United States and Russia could negotiate an ancillary agreement to New START (or its successor) capping the number of such weapons. 

Prompt Global Strike (PGS) is a United States military effort to develop a system that can deliver a precision-guided conventional weapon airstrike anywhere in the world within one hour. Today, there is no such system in the US inventory but technological advancements have made the notion of gliders and air-breathing vehicles flying at Mach 5 or faster significantly viable. The effort includes the X-15 rocket plane, the Boeing X-51 scramjet, the Hypersonic open Technology Vehicle 2 (HTV-2) program, the Hypersonic Air-breathing Weapon Concept (HAWC), and the Tactical Boost Glide (TBG). In July, the US and Australia concluded secret hypersonic flight series, which involved a Mach-busting missile flying eight times the speed of sound.

According to The Drive, in May 2017, the Defense Advanced Research Projects Agency (DARPA) hired Boeing to build what will likely be a solely rocket-powered hypersonic, reusable spacecraft, known as the XS-1. The Pentagon wants to test this design as a way of rapidly putting satellites into orbit, with an eye toward other roles in the future. The US military's goal is a space plane that can fly 10 missions in as many days while carrying a 3,000 pound load.

The military is pouring money into hypersonic research but the information is too scarce to make any conclusions about how efficient the programs are. The Trump administration requested $75 million for "hypersonic defense" in its fiscal 2018 budget as part of $7.9 billion overall funding plan for missile defenses. Capable both of maneuvering and of flying faster than 5,000 km/hr, hypersonic weapons could penetrate most missile defenses and to significantly compress the timelines for response by a nation under attack.

A landmark event took place in June. The unmanned subscale hypersonic SR-72 aircraft was reportedly spotted during flight tests in July. The follow-on step would be development of a full-scale, twin-engined SR-72. Program specifics are off limits as the development is a tightly-kept secret. There are few bits of open information that need to be pieced together to give at least the general picture of what it is.

The optionally piloted flight research vehicle (FRV) test is slated for 2018. Development of the FRV is expected to begin next year and first flights could occur as soon as 2020. The aircraft will roughly have the same proportions as its predecessor – the SR-71.

The proposed reconnaissance plane is expected to hit Mach 6 (7,400 kph) thanks to advanced new hypersonic technology. The SR-72 is to use a turbine-based combined cycle (TBCC) system to use a turbine engine at low speeds and a scramjet engine at high speeds. There is a breakthrough in the air-breathing side of hypersonics is the propulsion system to make it capable of outrunning missiles. With this speed, there is no need for stealth technology. The Skunk Works team in Palmdale, California, is doubling down on our commitment to speed,” said Orlando Carvalho, executive vice president of aeronautics at Lockheed Martin, speaking at the SAE International Aerotech Congress and Exhibition. “Simply put, I believe the United States is on the verge of a hypersonics revolution,” he added.

Besides spy missions, the SR-72 will have strike capability. The SR-72 flight testing follows the planned timeline for the hypersonic High Speed Strike Weapon.

To counter the threat, Russia applies efforts not to lag behind in hypervelocity capability. China does the same. Other nations are launching such programs. About 20 countries, including France, Australia, Japan and India, are already involved in the effort. The technology can be shared and exported. Like in case of nuclear weapons, the problem of proliferation comes to the fore.

The US is exploring the way to counter the hypersonic threat. For instance, the National Defense Authorization Act for Fiscal Year 2017 requires the Missile Defense Agency to “serve as executive agent for the Department of Defense for the development of a capability to counter hypersonic boost-glide vehicle capabilities and conventional prompt global strike capabilities that may be employed against the United States, the allies of the United States, and the deployed forces of the United States.” The problem is that air-breathing engine generates a very different signature from a rocket motor, meaning space-based surveillance assets might not be able to spot one as quickly or keep tracking it during flight, or even spot it at all for that matter. Super-fast flying cruise missiles or drones are extremely hard to counter as they are able to fly in more erratic ways well within the atmosphere, or even changing course in mid-flight.

The hypervelocity arms race is going on though very little attention is paid to the fact. The combination of hypersonic strike capability with a missile defense creates a temptation to deliver a first decapitating strike. An added danger is the potential marriage of hypersonic missiles with nuclear weapons. A weapon projectile flying at a hypersonic speed is too much for contemporary scanning surface- and airborne radars to track and process.

Once the technology is there, the race cannot be stopped but it can be controlled. The issue of hypersonic weapons control and non-proliferation is not included in the international agenda but it should be. As key players in the process, the United States, Russia, and China should launch discussions on the control of hypersonic technology capabilities. The existing arms control regime is gradually eroding, while new problems appear that should become a part of international security agenda but they are not. The overall deterioration of relations between the US and Russia, the US and China stands in the way of addressing burning arms control and non-proliferation issues. A looming hypersonic race is certainly one of them.

On May 7, the X-37B landed at NASA's Kennedy Space Center in Florida after a 718 days mission in space. All in all, there have been four missions since 2010, each lasting longer than the previous one. Launched atop Atlas 5 rockets, the vehicles land like airplanes. The twin reusable vehicles, also known as the Orbital Test Vehicle program, have amassed 2,086 cumulative days in space. The payloads and activities are largely classified. It is widely believed that the space planes are used for military purposes or are a weapon of some sort.

This X-37B carried at least two payloads on its latest voyage. The military revealed before the ship took off that it was carrying an experimental electric propulsion thruster to be tested in orbit and a pallet to expose sample materials to the space environment.

The unmanned X-37B resembles a miniature space shuttle. The vehicle is 29 feet (9 meters) long and has a wingspan of 15 feet, making it about one quarter of the size of NASA’s now-retired space shuttle. The unmanned robotic reusable vertical takeoff, horizontal landing spacecraft can re-enter the Earth's atmosphere and land autonomously. The robot can even adjust its course in space instead of following the same predictable orbit once it's aloft. The spacecraft's orbital endurance is enabled by its solar array, which generates power after deploying from its payload bay.

The altitudes used for military and exploration purposes today range from 0 to 20 km and from 140 km up. There is a void to be filled in between that is considered a potential theater of warfare. The X-37 is clearly a means to fill the void from «above» going down, while the Boeing X-51 (also known as X-51 Wave Rider) does it from «down» or from lower level going up. X-51 is an unmanned scramjet demonstration aircraft for hypersonic (Mach 6, approximately 4,000 miles per hour (6,400 km/h) at altitude) flight testing.

The X-37B project's total cost is unknown because the budget has been classified since it was transferred to the Defense Advanced Research Projects Agency (DARPA). It's almost certainly a spy plane, or, at least, a testbed for space surveillance gear and a launch platform for miniature spy satellites. The vehicle’s payload is enough to accommodate some spy equipment like cameras and sensors.

The vehicle has no docking hatch, so it cannot be used for small-size deliveries to the ISS or any other orbital station. It was also called a testing model for a future «space bomber» that will be able to destroy targets from the orbit. Some question whether the X-37B itself might be a delivery system for a nuclear bomb – whether the spaceship is intended to re-enter Earth's atmosphere on autopilot and dive-bomb an enemy target.

Dave Webb, chairman of the Global Network Against Weapons Nuclear Power in Space, said the X-37B «is part of the Pentagon's effort to develop the capability to strike anywhere in the world with a conventional warhead in less than an hour», known as Prompt Global Strike. Some surmise the X-37B is a satellite-tracker or a satellite-killer. Or both. 

It is generally believed that until now arms systems have not been stationed in space. Weapons of mass destruction are banned from space under the 1967 Outer Space Treaty. But the Treaty does not prohibit the placement of conventional weapons in orbit. No international agreement on non-nuclear arms in space has been reached due to the objection of some states, including the United States. The US argues that an arms race in outer space does not yet exist, and it is therefore unnecessary to take any actions.

The US ballistic missile defense systems, its X-37B space planes, airborne lasers and GSSAP (Geosynchronous Space Situational Awareness Program) spacecraft could be easily repurposed into weapons of space war. For years, Russia and China have pushed for the ratification of a legally binding United Nations treaty banning space weapons – a treaty that US officials and outside experts have repeatedly rejected as a disingenuous nonstarter. The United States does not come up with any initiatives of its own.

SALT I (1972), the first Soviet-American treaty on limiting strategic arms, included a mutual obligation not to attack spacecraft. In 1983 US President Ronald Reagan turned the tide by promoting the Strategic Defense Initiative that envisaged placing in space strike weapons to hit Soviet strategic missiles in flight. In 2002 President Bush Jr. abandoned the ABM treaty of 1972, which limited missile defense systems. Missile defense allows countries to develop offensive technologies under the pretense of defense. For example, Kinetic Energy Interceptors deployed in California and Alaska are launched into space to smash incoming missiles which presupposes the capability to destroy satellites as well. Obviously, the United States is ready to return to developing potential space strike systems, like, for instance, lasers, kinetic and particle beam systems.

The first ever draft Treaty on the Prevention of the Placement of Weapons in Outer Space, the Threat or Use of Force against Outer Space Objects (PPWT), was developed by Russia and backed by China to be introduced in 2008. The US opposed the draft treaty due to security concerns over its space assets despite the treaty explicitly affirming a State's inherent right of self-defense.

In December 2014, the UN General Assembly adopted a Russian resolution, 'No first Placement of Weapons in Outer Space'. The United States, Georgia and Ukraine were the only countries that refused to back the Russian initiative. Russia said it was prepared to work in the context of other initiatives, and had been an active and constructive participant in European Union-initiated activities on a draft International Code of Conduct for Outer Space. However, progress can only be achieved through fully-fledged negotiations with the participation of all interested States on the basis of a clear mandate under the auspices of the United Nations.

The current administration is bent on achieving space supremacy. Mark Wittington writes in a Blasting News article, «One of the significant changes that the incoming Trump administration is contemplating in defense is the development of space-based weapons». It adds, «One idea that has kicked around for decades is a system that would consist of a tungsten projectile and a navigation system. Upon command, these ‘rods from God’ as they are poetically called would re-enter the Earth’s atmosphere and would strike a target».

President Trump’s policy advisers Robert Walker and Peter Navarro call for bringing the «Star Wars» concept back. They want the president to make the US lead the way on emerging technologies that have the potential to revolutionize warfare. According to them, an increased reliance on the private sector will be the cornerstone of Trump’s space policy. Launching and operating military space assets is a multibillion-dollar enterprise employing thousands, spurring innovation, spinning off civilian applications like GPS, and fueling economic growth. Defense Secretary James Mattis calls for bigger investments into space exploration for defense purposes. A provision to encourage the Defense Department to start a research program for space-based anti-missile systems was inserted into the 2017 defense authorization bill.

The weaponization of space will undermine international security, disrupt existing arms control instruments and entail a string of negative effects (things like space debris). It may spark a devastating arms race distracting resources from the real problems faced by humanity today. Strategic stability would be destroyed because space weapons are global in scope and capable of covert and surprise attacks on any point on the planet at any point in time. The deployment of space-based technologies will result in the rejection of new treaties to regulate nuclear weapons and their delivery systems.

This year the world marks the 50^th anniversary of the Outer Space Treaty, which entered into force in October 1967 – an arms control deal reached in the heat of the Cold War. It was possible then, it is possible today. The issue of preventing weaponization of space through an international treaty should become part of the Russia-US-China agenda. If these states come to agreement on the issue, the world would become a much better place.

And how does the US military envision «countering Russia and China»?

Back in the 1970s, the balance of power in the world looked like this: the USSR and the United States maintained approximate nuclear parity, up to the level of mutual assured destruction. The 1972 ABM treaty slowed the arms race, reduced the risk of a third world war, and introduced a crucial principle that enabled the 30-year standoff between the Soviets and the Americans to proceed fairly uneventfully – this was the agreement between the parties to restrict their missile defense systems, based on the understanding that vulnerability to a retaliatory strike is the most reliable means of deterrence.

And since then, virtually all of American history can be seen as a series of unceasing efforts to circumvent those agreements. «Star Wars» was a failure: The US could not find a way to technologically evade the mutually assured destruction it so feared. The idea of erecting orbital deployment platforms armed with lasers and kinetic interceptors was a flop… The Americans found more success during the era of Gorbachev and Shevardnadze by destroying Soviet intermediate- and shorter-range missiles without a proportional reduction in US military might.

The next steps were attempts to circumvent the ABM Treaty, which culminated in the unilateral US withdrawal from the treaty on the pretext of threats – not from Russia, but from «rogue states». The ABM Treaty was finally terminated on June 12, 2002. Shortly before that, in 2001, the UN General Assembly passed a resolution, supported by over 80 countries, in support of that treaty. Only the US and Israel opposed it.

Even then, a pattern could be discerned in America’s diplomatic and propaganda efforts in this realm: the demonization of «rogue states» and the wild exaggeration of the actual threat they represent. This was a change that deserves some examination: for many decades prior to this, US and Soviet negotiators precisely calculated each side’s military capacity and arrived at figures that were acceptable to both parties, but in the 21st century the United States began to unilaterally gauge the military potential of North Korea, Iran, and Iraq. And Washington also unilaterally chose its own ways to counter these «threats». In Iraq in 2003 this course of action by the US culminated in an intervention.

The year 2015 presented an interesting situation. As the time neared for the signing of an agreement on Iran’s nuclear program, which would mean losing their official rationale for continuing the work on their new missile defense launch sites, American diplomats embarked on two new steps. First: it was announced that the US would continue its missile defense work in order to prevent unemployment («to engage that sector of industry»). Second, there was an attempt to circumvent the principle of mutual assured destruction and to disregard the right to equal security, by advancing the concept of Prompt Global Strike – a non-nuclear attack on any location on the planet.

What is truly new about this plan?

1. Prior to this, US cruise missiles – guided bombs with non-nuclear warheads – could not inflict significant damage on the nuclear forces of the USSR/Russia. But in wars since 1991 (in Yugoslavia and Iraq) strikes from a great distance away have already been tested.

2. The key word in the phrase Prompt Global Strike is «prompt». An attack can be delivered within one hour.

Russian Deputy Prime Minister Dmitry Rogozin has commented that «the concept of Prompt Global Strike, which is being developed in the US, offers the chance to gain the upper hand over a nuclear state, thanks to these weapons’ first-rate technical specs, including their superior speed. Specifically, these would include aerial vehicles (including drones) and missiles capable of traveling 6-20 times faster than the speed of sound».

Prompt Global Strike technologies include intercontinental ballistic sea-based Trident II (D5) type missiles carrying high-precision non-nuclear warheads, as well as the hypersonic cruise missiles the Americans are testing, plus other hypersonic vehicles (the Falcon HTV-2 and AHW). The designers believe that it is possible to forgo equipping such aircraft with any warhead at all, since their speed and energy will be sufficient to destroy any target with a direct hit. A hypersonic, long-range cruise missile is capable of reaching its target 5-6 times faster than a subsonic Tomahawk missile.

Another means of inflicting a Prompt Global Strike is through the use of kinetic weapons. These consist of heat-resistant tungsten rods that are dropped on a target from a great height. During their tests, the Americans concluded that a rod six meters long and 30 cm thick that is let loose in the direction of a target at a speed of 3,500 m/s will release an explosion of energy equivalent to 12 tons of TNT at the point of impact!

This means that in the event of an armed conflict with a country possessing nuclear deterrent forces, time will truly be of the essence. Speed and surprise will determine everything. The strategy for announcing such actions could be based on the claim: «he who first launches a nuclear weapon should be the one viewed as the aggressor!»

One hour – sixty minutes – is all the time one has to make a decision about using Prompt Global Strike. This means that the concept of the threshold of a nuclear war is becoming blurred, which necessitates a change in the decision-making mechanisms…

Perhaps this is precisely what Russian Deputy Foreign Minister Sergey Ryabkov meant when he said: «The development of the Prompt Global Strike system in the United States could result in a conflict with apocalyptic consequences».

Over a decade ago, in its effort to maintain military superiority and a powerful deterrent, the United States identified the need for a new capability. This led the U.S. military to create the controversial concept of a high precision global strike capability. The program is currently in the research and development phase and mainly boils down to the development of long‐range high‐precision conventional weapons capable of reaching a target anywhere in the world within one hour. The Obama administration has indicated that it intends to make an acquisition decision till the end of the term. 

The Prompt Global Strike (PGS) program encompasses numerous technologies. The potential components are conventional intercontinental ballistic missiles equipped with high-precision, non-nuclear warheads, strategic cruise missiles with hypersonic speeds or an air-launched hypersonic cruise missile, such as the Boeing X-51 or Advanced Hypersonic Weapona and kinetic weapons which are yet to be implemented in practice. The Air Force and DARPA are developing a hypersonic glide delivery vehicle that could deploy on a modified Peacekeeper land-based ballistic missile—a system known as the Conventional Strike Missile (CSM). Congress may review other weapons options for the PGS mission. These include not only ballistic missiles and boost-glide systems, but also bombers, cruise missiles, and possibly scramjets or other advanced technologies. In addition, once the Obama administration has committed to a competitive acquisition process, industry may also submit additional ideas. The US aims to combine PGS with its space and anti-missile technologies to form an integrated defense system, which could render other countries’ strategic weapons, including nuclear arms, almost useless. 

There are some tangible achievements on the way. On May 1, 2013 an experimental unmanned aircraft developed for the US Air Force has flown at more than five times the speed of sound in a test off California. The test marked the fourth and final flight of an X-51A by the Air Force – a breakthrough in scramjet technology. The aircraft achieved the velocity of Mach 5.1 (4828 kmh) at 60,000 feet (18,288 meters) making it hypersonic. It traveled 230 miles in little over six minutes. The vehicle plunge into the ocean as planned. 

The X-51A aircraft is known as the Wave Rider because it stays airborne, in part, with lift generated by the shock waves of its own flight. After being dropped from a B-52 bomber, a solid-rocket booster is used in the initial phase of the plane's flight to accelerate it up to the speed which allows the engine to take over by drawing in air through the craft's forward momentum. Achieving a successful scramjet flight is very technically challenging because of the high speeds and temperatures generated.

The Wave Rider is designed to reach speeds of Mach 6 or above, six times the speed of sound and fast enough to cross the Atlantic Ocean and strike a target in Europe in less than an hour. The US Air Force will continue hypersonic research and the successes of the X-51A will make a contribution into the High Speed Strike Weapon program currently in its formation phase.

X-51 is in no way a competitor for a conventional Trident. It will have a range of only 600 nautical miles. And it first needs to be lifted into the air by a plane, and then accelerated by a rocket-fueled booster before its hypersonic engine kicks in. But it is the first weapon other than a ballistic missile to fly at hypersonic speeds.

In his recent book Silver Bullet? Asking The Right Questions about Prompt Global Strike James Acton, Senior Associate in the Nuclear Policy Program at the Carnegie Endowment for International Peace argues for a wider debate over the merits and demerits of the system. There are several destabilizing factors inherent to the program, such as its reliance on the development of long-range missiles with conventional explosives in the place of nuclear warheads, which could easily lead a state to mistake a CPGS weapon for a nuclear warhead, the potential ambiguity carried with it poses a considerable threat to strategic stability. 

There is another aspect of the problem. Long-distance launching vehicles for precision-guided conventional warheads and non-nuclear boost-glide weapons are not covered by any agreements. The issue is not included into the security and arms control agenda. It may spark a new arms race. Other countries have no way out but to meet the challenge they face and they do. The concerns are very real, the above mentioned facts prove that the efforts are already in progress. There may be profound implications for international security if the issue is not addressed in time.

Discussions within the United States about using CPGS weapons to attack hard and deeply buried targets inevitably raise concerns in Russia about the survivability of silo‐based intercontinental ballistic missiles. Russian officials have expressed their sharp criticism towards the U.S. plans for the PGS initiative. 

On June 19, 2013 – just hours before President Barack Obama called for further nuclear reductions in Berlin – President Vladimir Putin issued a preemptive rebuttal, stating that, «we see that work is active around the world on developing high‐precision conventional weapons systems that in their strike capabilities come close to strategic nuclear weapons. Countries that have such weapons substantially increase their offensive capability».

Following the meeting of the Russian Ministry of Defense collegium in Moscow on December 10, 2013, the Defense Minister, Army- General (five stars) Sergei Shoigu, and the chief of the General Staff, Army-General Valery Gerasimov, instructed the top brass on the priorities facing the military. Top commanders were told that the development of Prompt Global Strike one of the major threats the defense plan is linked to. 

A plan is being drafted to deploy rail-mounted nuclear missiles as a potential response to Prompt Global Strike. On December 18, 2013, Lieutenant-General (two stars) Sergei Karakaev said, «A defense ministry report has been submitted to the president and the order has been given to develop a preliminary design of a rail-mounted missile system». Karakaev added that extensive analysis of the US system led to the conclusion that «there is a need to reconsider the issue of a rail-mounted missile system given its increased survivability and the extent of our railway network».

«If we are talking about existing ballistic carriers with conventional equipment, it is clearly the path to the escalation of the conflict with the hardest, in fact, apocalyptic consequences», said Deputy Foreign Minister Sergei Ryabkov.

Russian Deputy Prime Minister Dmitry Rogozin said last December that Moscow reserves the right to use nuclear weapons in response to a conventional strike and sees them as a «great equalizer» reducing the likelihood of aggression… Rogozin said that those who «experiment with non-nuclear strategic weapons» should remember that «if we come under attack, we will undoubtedly use nuclear weapons in certain situations to defend our territory and state interests».

The leaders of US and Russia know how to be wise and insightful. That’s how the 1972 ABM and INCSEA, SORT and START treaties were signed and anti-satellite experiments were put on the shelf. Isn’t it time to revive a bit of the past? Other states like China could be included into the arms control process making it a much better alternative to an uncontrolled arms race.