The violence, global outreach and the scale of the casualties suffered by countries participating in World War One have created a belief that the nightmare cannot be repeated. The League of Nations, inspired by President Wilson, was to become the assurance of peace. And although the United States finally chose isolation, the war-tired countries of Europe wanted to believe in a peaceful tomorrow. But peace was not destined to the twentieth century. The economic crisis of the early 1930s was a herald of the looming storm and was largely its cause. For the USA, late and somewhat forced participation in the war seemed to be a great business. The period of post-war economic recovery allowed President Hoover to announce the eradication of poverty. A little prematurely; on 24 October 1929 a joint action of the greatest bankers of the era managed to prevent the collapse of stock exchanges, but only five days later it turned out that they were not gods of money either. The period of prosperity preceding the collapse democratized the financial markets, so the turmoil of the “Black Tuesday” strained the fortunes of the great and annihilated the savings of the little ones. Beginning in the USA, the economic crisis started a march that soon encompassed most countries of the world. Everywhere it was accompanied by a wave of bankruptcies, rising unemployment and the dramatic aggravation of social problems, scrupulously exploited by political extremists.