How did america get involved in WW2?

I'm not going to answer all your question, because it's far to large a question and too complex, but I will correct you on a point or two. The US didn't declare war on Germany until after Germany had declared war on the US (December 11th). The US was aiding our ally, Britain, in some ways, and was selling food and other goods to her, and the Germans were, increasingly, willing to risk war with the US in order to try to stop food from getting to Britain. They were pushing the matter, and would, eventually, have ended up pushing us into war anyway. But Hitler's declaration of war, despite the fact the Axis alliance did not require him to do so, made it easy.

Reluctantly.

It took a while but once we did... no one could stop us.

I mean if you look at the sea of barges we sent to Normandy just for that beach landing it was as far as the eye could see.

I don't know why the Germans even bothered.

Pride, I guess.

After the US declared war on Japan, the Nazis honored their defense pact with their ally and declared war on the US. It was only after the Nazi declaration of war that the US declared war against them.

You say you did research but clearly you didn't as GERMANY declared War on America just days after the Pearl Harbour attack and German Subs started sinking ships alone the American East Coast.

Pearl Harbor was really the deciding factor. Up until then Roosevelt, the US congress and in general the people did not wish to be involved for mostly economic reasons; so remained neutral. Churchill asked Roosevelt for assistance several times, but none had been forthcoming. There was also much pro-Nazi sentiment in the US (as well as in the British royal family itself; another story). Pearl Harbor meant that the US was actually forced to participate.

On 11 December 1941, four days after the Japanese attack on Pearl Harbor and the United States declaration of war against the Japanese Empire, Nazi Germany declared war against the United States, in response to what was claimed to be a series of provocations by the United States government when the US was still officially neutral during World War II. The decision to declare war was made by Adolf Hitler, apparently offhand, almost without consultation. Later that day, the United States declared war on Germany.

The Japs attacked Pearl Harbor on December 7, 1941, and the United States declared war on the Japs on December8, 1941. Even after Pearl Harbor, there was no strong sentiment among the American people to go to war with Germany. Then, on December 10, 1941, Hitler then pulled a very stupid move. He declared war on the United States. Well, okay, the United States returned the favor, declaring war on Germany on December 11, 1941, and the war was on.

To earn a lot of money.

muy fuertes

Chances are he was changing his mind as time went on, he realized if we let all out allies get taken over eventually we would not be able to stand against the AXIS powers. Once we realized we were vulnerable despite the ocean between Japan and the US, we realized the same would apply to the east coast. then Germany declared war on us. Therefore the US went after the Nazis in Europe first, so we would not face two fronts. We allied with Russia to force the European war to be on two fronts. https://www.history.com/this-day-in-history/german...