Russian Prime Minister Dmitry Medvedev said his country is in a new cold war with the US and its allies, while NATO's chief said Russia is using its nuclear arsenal to intimidate Europe. The clash, with echoes of superpower rhetoric during the 20th century, played out at the Munich Security Conference on Saturday even as Russia, Europe and the US say they're seeking to end Syria's civil war, resolve the armed standoff in eastern Ukraine and make progress toward lifting European economic sanctions against Russia. "The political line of NATO toward Russia remains ...