President Putin says Russia will soon be first to deploy 'invincible' hypersonic missiles.
He says the Avangard weapon guarantees Russian security for decades to come.
Supersonic is slow compared to hypersonic.
Flying at many times the speed of sound, they're are designed to evade missile shield systems to strike anywhere in the world.
Wednesday's test-firing hasn't been independently verified.
But with the United States, China - and possibly others - developing similar technology, how big a threat are the new, high speed weapons?
Guests: Tarif Rauf - Nuclear arms control specialist
Pavel Felgenhauer - Russian defense analyst
Richard Weitz - Director, Center for Political-Military Analysis, Hudson Institute