History Alert - After the launch of Sputnik, Soviet leader Nikita Khrushchev bragged that his country's factories “were turning out missiles like sausages” and greatly exaggerated the size and operational capabilities of the Soviet ICBM force.
In reality it matters not if the U.S. knew before hand or not. A multi nuclear missle launch (with the old rockets they have) will annihilate anything and everything. Russia will not just send one invisible missle. It's all or nothing if that scenario ever happens. Even if they did just try and destroy the U.S. and succeed every other country on the planet will launch their nukes at them.
Just the same old scare tactitcs from the plutocratic playbook.