The expiration this week of a core U.S.-Russia arms control treaty could touch off a global nuclear weapons race for the first time since the Cold War.
Russia made initial overtures about a renewed pact in September, but the Trump administration has not formally responded, according to two people familiar with the negotiations. The New START treaty, which will expire on Thursday, was struck in 2010 and limited how many deployed nuclear-capable missiles, bombers and warheads both the U.S. and Russia could have...
