In November 2011, Moscow threatened to deploy tactical nuclear weaponry in Kaliningrad in response to US Missile Defense (MD) radar systems to be deployed in Turkey. Although Washington argued that MD systems are intended to counter Iranian missile systems, Moscow still regards the fourth phase of the Phased Adaptive Approach as potentially threatening to Russia itself. Moscow additionally stated that it might quit New START after the US dropped out of the adapted Conventional Force in Europe (CFE) treaty.