USA's main purpose for getting involved in the French/Vietnamese war was was not to 'kill 5 million' vietnamese as you stated. It was just a nasty by-product of a vicious war.

In hindsight, the USA's politicians should never have gotten involved since the majority of Vietnamese considered it a war of liberation from a european colonial power... not very different from when the 13 american colonies fought the british.

I was under the impression that the treaty of versailles was the most important aspect of the reasoning behind the beginnings of ww2.. as Darken said. Part of the bring back of "the glory of germany"..

I thought Germany was doing great before they entered the war, they had climbed out of the mud pit ww1 had left them in..

the allies were hated, as were the jews and communists.. because they brought down the the great glory .. and caused sufering.. -the results of the treaty-.. and results of the invasion and over taking of german economy from the jewish people.. I think perhaps the treaty is a very important part of the beginning...

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The past is what makes us who we are dont make it your burdern

First, I think it is a huge mistake to believe that the way WW1 ended isn't the biggest factor in why WW2 began. The Treaty of Versailles humbled Germany. It forced huge reparations, which the Germans couldn't afford to pay, and caused huge levels of inflation. (We have all seen the picture of the wheel-barrow full of money to buy a loaf of bread.) It stripped Germany of valuable land. It forced Germany to disarm. It forced Germany to take full responsibility for the war. What's more, it came after a civilian government took power, giving the impression to many German's that they had been sold out. Remember. It wasn't like Germany accepted armistace at the point of disaster. They were still on French soil. In fact, no American commander thought that the armistace would last long-term.

Given these circumstances, Hitler's message of German nationalism was very powerful. German's felt that they were screwed needlessly after the first war. If you couple this popular feeling with the financial interests in Germany that would gain from military expansion I think you get a better idea of why powerful Germans wanted Hitler (despite the fact that they knew he was hair-brained leader) in power.

As far as why Germany attacked Russia (I'll use this instead of the Soviets), there are two reasons. One was that they would have eventually had to fight. Everyone knew that the non-agression pact would only buy about 5 years of peace at the most. Russia was on the upswing industrially and militarily, and would be the one nation that could pose a threat to Germany in Europe. Communism has little to do with anything. The other major reason for the attack of Russia was resources. More specifically: oil. Russia was the gate to invading the Middle East/Asian oil fields. Had the Germans suceeded in getting oil it is likely that they could have held out for a year or two more. Had that happened, it is likely that they would have had the bomb shortly after the Americans, and that changes the entire dynamic of the war.

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Any man who can render himself unconscious with a pretzel isn't smart enough to lead the free world.