Russian authorities have stepped up nuclear-war survival measures amid a showdown with Washington, dusting off Soviet-era civil-defense plans and upgrading bomb shelters in the biggest cities.

At the Kremlin’s Ministry of Emergency Situations, the Cold War is back.

The country recently held its biggest civil defense drills since the collapse of the U.S.S.R., with what officials said were 40 million people rehearsing a response to chemical and nuclear threats. Continue Reading.