In the mid-1930s they began rearming Germany, recruiting hundreds of thousands of soldiers into the military and building thousands of tanks, fighter planes and bombers.
Although Britain was rearming rapidly, the rearmament programme would not be complete until 1941, and in the meantime, Chamberlain continued in his efforts to preserve peace through diplomacy.
Short of a promise to defend Ukraine directly, ideas include the ability to " snap back" any sanctions on Russia that are lifted; and rearming Ukraine quickly if it is attacked again.