What most Russian miracle weapons have in common is that they do not work as intended. The Kinschal hypersonic missile is not even a hypersonic weapon; the nuclear-powered Burevestnik cruise missile only completed three of 14 tests successfully, but left massive radiation in the test area. With the Poseidon nuclear torpedo, it is questionable whether the concept can work like this. Now it is the Sarmat that is supposed to cause fear and terror in the West. After all, it is an intercontinental ballistic missile with a range of 18,000 kilometers.
