Targeting the enemy: Radar, radio control and inertial-guidance systems helped improve the accuracy of both offensive and defensive weaponry

After June 1940, only 10 months into World War II, Britain was on its own in Western Europe, with little more than its narrow strip of sea holding off Germany's vastly superior military strength. France had capitulated under the Blitzkrieg — the lightning war — and the remnants of Britain's disarrayed army were forced off the French beaches at Dunkirk, under the strafing guns of the Luftwaffe, the German air force.