As it was the Cold War which meant that neither side was willing to attack the other as both sides had atomic weapons aimed at the other. This would lead to a nuclear war
Assuming you're referring to the Palestine Riots of 1929, the best option would be "religion," since the main cause was a rivalry between Muslims and Jews of access to the West Wall.
Adolf Hitler, because he was their leader and promised the German people a better future.
During World War II
