I agree with Charles, Lenin, as leader of the Russian revolution shaped the twentieth century, Hitler was merely a reaction to the great steps forward that came through Lenin's challenge to imperialism, and so deserves only a secondary role.
The African nationalist Thomas Sankara was wont to say that the French revolution made freedom an ideal, but the Russian revolution made it a practicality - and so it was that the liberation of the colonies was set in motion: surely the single most important movement of our century.
But, for sheer perversity, can I also suggest the following. The second most progressive influence in the twentieth century has been, doubtless for all the wrong reasons, Japan.
Japan's exclusion from the white man's club of imperialists forced this capital-exporting nation to challenge the existing order of Anglo- American domination of the world. It was Japan that demanded a clause in the 1919 League of Nations Charter against racial discrimination.
Japanese victories over European armies (Russia in 1905, Britain at the Fall of Singapore, and America in Pearl Harbour) smashed for all time the myth of White Supremacy that kept the colonies under the heel.
Clearly the record of the Japanese territories in 'Manchuko' and Korea argues that this was no liberation army. But to paint the Japanese as 'just another imperial power' misses out the extraordinary ideological and moral impact of the defeats inflicted on European colonialism by a non-white army.
(In fact, British leftists have always talked up the viciousness of the Japanese colonialism the better to drown out the cries from Britain's own colonies.)
The pro-Japanese Indian National Army under Subbhas Chandra Bose was in truth, not a force of any great weight. But the propagandistic appeal of Bose's INA made Indian independence unavoidable. So too the defeat of the British Empire in the East meant that it was impossible to re-impose colonial rule after the war.
Ho Chi Minh was a US contact during the Second World War, reporting back to the State Department on the struggle against the Japanese. But the fact of the Japanese defeat of the Europeans meant that Vietnam would not be willing to accept a return to the old order.
Nationalist movements throughout the far east fought against Japan, but in doing so they were establishing their independence, not a return to their prior subservience to the West. The legacy of Japan's challenge to White Supremacy in the East was a liberation from colonial rule.
So, my second nomination for most influential would be Tojo, followed by Mao and Ho Chi Minh. -- Jim heartfield