The new arms race is hypersonic

Dan Winters for The New York Times

Revolutionary weapons that are under development in the U.S., China, Russia and other countries will have the capacity to travel at more than 15 times the speed of sound, to strike before any sonic booms or other meaningful warnings reveal their presence, and to penetrate any surface with the force of three to four tons of TNT.

The rush to possess these weapons has created a new arms race that could upend deterrence norms and renew Cold War-era tensions.