Why did US finally decide to enter world war 1?

Answer 1

Propaganda. The British used propaganda depicting German war atrocities to win American support. The British deployed their navy to blockade Germany and keep it from obtaining supplies. The British planted mines in the North Sea and force neutral ships to go under inspections incase the ships were providing transportation of valuable materials to Germany or its neighbors. The British also expanded the definition of 'contraband' to prevent neutral countries from shipping food to Germany. Since Germany knew that the Allies depended on food, equipment, and other supplies from the U.S. and overseas empires, Germany decided to starve the British and French into surrendering. First, Germany had to get around Britain's blockade. To do that, the Germans deployed submarines called U-boats. Second the Germans said they would attempt to sink every vessel without warning that they found in the waters near Britain. This made the U.S. very mad. Germany had sunk Lusitania and Sussex, killing Americans. Then the Sussex Pledge was created so Germany could no longer sink merchant ships without warning. This kept the U.S. out of the war a little longer until Arthur Zimmermann (German official) cabled a German ambassador in Mexico, commanding him to make an offer to the Mexican government. Zimmermann proposed that Mexico ally itself with Germany and the U.S. and in return Mexico would regain its "lost territory in Texas, New Mexico, and Arizona" after the war. "Germany hoped Mexico would tie down the American forces and prevent them from being sent to Europe." Then the British intelligence intercepted Zimmermann's telegram and shortly it was leaked to American newspapers. This made American even madder and concluded that it was necessary to begin war with Germany. Third, (February 1, 1917) Germany went back to unrestricted submarine warfare. They thought that in 4 to 6 months that Britain would surrender, but never realized the U.S. would actually be able to enter into war in 6 months because the U.S. would have to raise an army and transport troop to Europe. April, 6, 1917, President Wilson signed the resolution that concluded that America was at war. If you do the math, Germany thought it would take at least 6 months for the U.S. to be able to enter the war, but it only took the U.S., from February 1, 1917 to April 6, 1917 which is 2 months and 5 days to get a resolution signed to determine that America was officially at war.

Answer 2

It's more the other way round. The USA would not have entered WWI at all unless its interests were threatened. At that time, as at many times, the USA was isolationist, did not want to get involved in other nations' problems.

Answer 3

Germany was sinking the US's ships.

Answer 4

They didn't enter the first world war