Russia concerned about hypersonic missiles being able to threaten its nuclear deterrent

Russia, the United States, China, and India are leading development of hypersonic missiles. These missiles are intended for launching high-precision non-nuclear strikes against a range of targets and carrying them out in significantly less time than existing cruise missiles.
Russian officials and experts believe that hypersonic weapons deployed by the United States will drastically increase the effectiveness of the global strike concept and give Washington a capability to deliver a disarming non-nuclear strike against Russia’s Strategic Nuclear Forces.
Russia had a hypersonic glide design study [called Albatross] in 1987. The design was relatively simple: At boost phase, the UR-100N UTTKh (SS-19) intercontinental ballistic missile (ICBM) would launch a so-called hypersonic gliding vehicle (HGV) to an altitude of 80 to 90 kilometers, after which the HGV would make a low-angle turn toward the earth’s surface and accelerate at a descending trajectory, gliding to intercontinental range at hypersonic speed, or five times the speed of sound. An HGV armed with a nuclear weapon would supposedly make rapid cross-range maneuvers to circumvent ground-based U.S. missile defenses.
The Albatross was developed to defeat orbital SDI [Reagan antiballastic missile Star Wars] technology, ironically, the HGV is vulnerable to conventional anti-ballistic missiles weapons such as the Patriot PAC-3 or the THAAD
China has conducted six tests of its hypersonic WU-14 missile in a span of just under two years, starting in 2014.5 The WU-14 is a hypersonic gliding vehicle launched by a ballistic missile that, according to reports, may carry both conventional and nuclear weapons.
During one test, the aircraft demonstrated a high degree of maneuverability that would enable it to penetrate the enemy’s missile defenses, which suggests that the Chinese aircraft almost fully replicated the design and flight pattern of the Russian Albatross HGV.