The act of raising one's hands, palms facing out, with the index and middle fingers displayed as a sign of triumph (Nixon-style) likely has its origins in World War II. As the story goes, good old Winston Churchill was coming out of a very important meeting with the high-end members of Parliament. Unfortunately, I cannot say exactly when the meeting took place. It might have been after Germany's invasion of Poland on August 31, 1939, or after the Luftwaffe's first bombing of London. In any case, the prime minister was asked what the decision (of the meeting) was. Being a man of few, yet highly poignant words, Churchill merely raised two fingers, palm out.
The British Press took this to mean that Churchill was promising victory for Britain, defiantly waving a V to the enemy. The press was right about Churchill being defiant, but was slightly off-color about the meaning. Churchill, some say, was in fact making a reference to the Hundred Years War (see History of "The Finger" for a more detailed explanation from various points of view). By showing the "V" he was stating that the decision was to fight, not necessarily to win. British archers, it is said, used to hold their fingers in the air in the same manner as a way to say to the French, who would render captured archers useless by cutting off those fingers, "We still have our fingers, we will still fight."
Corrections, factual error reports, comments greatly appreciated.