The sinking of the ____________ and germany’s continued use of unrestricted ___________ warfare brought the united states into the war in 1917.

Respuesta :

I am not 100% on this so you may want to fact check my response: 

Lusitana - it was torpeded by German U-Boats and it sank in 18 minuntes... i also believe it was a passenger ship which also really upset the US
submarine- new