Why the United States entered WW1 on 1917?

Question: Why the United States entered WW1 on 1917!?
Best Answer - Chosen by Asker:

Feels free to visit: http://www!.sparknotes!.com/history/europe!.!.!.
This site include the sequence of events about why "The United States Enters the War"!.
Simple & Informative!. Easy to understand!.

Cheer up your day! ^^Www@QuestionHome@Com

Because they tried to stay out of it and stay neutral but they couldn't!. Germany sunk the Lusitania and killed Americans!. That was the last straw!. We had to defend the Americans!.Www@QuestionHome@Com