All ICBM reach near-orbital velocities (~7.8 km/s, ~17,000 mph, ~Mach 23), including the Russian R-7 (the world's first ICBM in 1957) and the modern ICBMs on wh

All ICBM reach near-orbital velocities (~7.8 km/s, ~17,000 mph, ~Mach 23), including the Russian R-7 (the world's first ICBM in 1957) and the modern ICBMs on which Russia's Avangard hypersonic glide vehicle will ride. This is only possible while outside the atmosphere. The difference is that the traditional re-entry vehicles quickly slow down to mere supersonic speeds (Mach 1-5) when they re-enter the atmosphere, making them somewhat more vulnerable on final approach. Hypersonic glide vehicles, in contrast, maintain hypersonic speeds (Mach 5-10) until very late.