Why did the US enter World War 1 Late?

Answer 1

In the early 20th century, the US was still largely isolationist as the American people had no appetite for foreign wars. The sinking of the cruise ship Lusitania turned public opinion in favor of war, allowing US leadership to enter World War 1 alongside its allies.

Answer 2

The cruise ship RMS Lusitania was sunk by Germany killing 1198 people, among whom were 128 Americans. This act, along with the release of the Zimmermann Telegram in 1917, galvanized the American people into supporting entry into World War 1.

Answer 3

One of the reasons was the British interception of the Zimmerman Note or Zimmerman Telegram. This was when Arthur Zimmerman telegraphed the Germany ambassador in Mexico to tell Mexico to be Germany's Ally. In return, Germany would get Mexico back their lost territory in the US in the states of Arizona, New Mexico, Texas, Nevada, California, and other surrounding states.