im a little hazy on American history but i believe America sided with the allies because Austria(or Germany can't remember) invaded...Serbia i think or Poland im not sure anyway the Black hand gang only Asassinated the Arch-Duke because their homeland was being occupied by ..Austrian(or German lol) forces a lot of this info is a less than credible so any corrections are welcome. besides the cause of world war 1 is always being debated

The americans entered WW1 due to the sinking of the ocean liner Lusitania by a german u-boat. Some 200 americans lost their lives. the Germans claimed it was carrying ammunition to england to be used in the war against them. the US denied this and used this incident as a reason to declare war against germany. It might be noted however that the united states had been siding with the allies pretty much from the beginning.

There were many factors. first of all America were already siding with the alies and sending them supplies. Then Germany started sinking American ships with thier U-boats. After negotiations with Germany they agreed to stop sinking American ships. Later, Germany sank the Lusitania, and while is wasn't an american ship, there were many Americans on board, but that didn't quite lead to war yet. Secondly, Britain intercepted a telegraph from Gemany's Ambassador to Mexico, (Alfred?) Zimmerman saying that if Mexico joined the war on their side, they would make sure Mexico got all the land that they lost in the Mexican-American war back (including but not limited to: California, Arizona, New Mexico, Texas, and most of Colorado), but thad didn't quite lead to war either. Thirdly, during negotiations with Germany concerning the sinking of American ships and Germany agreed to let through one American ship per week if the ship was painted with red and white zebra stripes to mark it's neutrality. That was the last straw, those f***ing ba*****s are going down! But then it took us almost a year to get any troops to Europe and only managed to get 2,000,000 out of 5,000,000 troops over there throughout the course of the war.

Three words UNRESTRICTED, SUBMARINE, WAREFARE!!!!!!11111

The main reason is that they were pulled into it by the Zionists in a deal they made with Britain to take possession of Palestine after the war. The Balfour Declaration was the secret agreement that guaranteed Britain would keep its part of the deal (Britain is not known for its integrity). [] The sinking of the Lusitania was avoidable - the United States was supporting Britain illegally. They were smuggling armaments and ammunition on the Lusitania - it was illegal to carry military weapons on civilian ships. Germany knew what the Allies were doing and even sent warnings to the shipping company cautioning passengers not to take the Lusitania. [] The Zimmermann Telegram was a false flag made up by the British. They intentionally allowed it to "slip" into US hands in an effort to get them into the war. [] Had it not been for the Soviet Union, there would never have been a WW1. After the conflict between Serbia and Austria was triggered by the assassination of the Arch Duke, the Soviets threw their support to Serbia. Germany warned the Soviets to stay out of it - otherwise, they would be forced to back Austria. The Soviet Union ignored Germany, which pulled Germany into the middle of it. Britain then sided with the Soviet Union (without cause - they had no dog in the fight), and France backed Britain.