The initial plans saw the defence of Western Europe from a Soviet invasion resting heavily on nuclear weapons ('Massive retaliation'), with conventional forces merely acting as a 'tripwire.' The policy enunciated in Military Committee document MC14/1, issued in December 1952, saw the defence of Germany as principally a delaying action, to allow a line of resistance to be established along the lines of the IJssel and Rhine rivers. The conventional forces would attempt to hold this line while the allied strategic air forces defeated the Soviets and their allies by destroying their economy and infrastructure.