World War one
Why USA entered the War
you should already know that the USA was just going to handle it's own problems and not deal with other problems. This is called isolationism . Although they were isolated, it wasn't for long. a German submarine torpedoed the Lusitania, a British steamship, and killed over 100 US citizens. Then the Americans called for war.
Tecnologies and Weapons used in the War
There are many technologies and weapons used in the war to end all wars. some weapons include poison gases, air planes, and heavy artillery. Back then, air planes were not used as weapons until this war.
The war ends
On November 11, 1918 the central powers surrendered. On January 1919 the treaty of Versalies was created. Germany was not invited. with that information, you should know this is not over.