The potential threat of conventional Prompt Global Strike (PGS) by the United States is one of the top challenges for the Russian military. For instance, launching a missile in a flatter arc involves a shorter flight time to target and gives less time to detect and react to an incoming attack. If boost-glide vehicles are launched, radars would confirm satellite signals too late for a launch-on-warning. US developments in intercontinental-range hypersonic weapons pursue the goal of giving Washington the ability to disarm Moscow without resorting to a nuclear first-strike. The PGS system is designed to strike the most significant fixed site and mobile targets, including well-protected command posts, silo and mobile launchers of ballistic missiles, etc. Russia has to take steps to develop defense systems and its own hypersonic weapons to counter the looming threat. Its effort to accomplish this mission has proven to be quite a success.
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.