How did u-boats affect american neutrality?

The German U-boats blocked British Isle and attacked merchant ships affecting the trading business of US with British, but at some stage the U-boats started to attack ships taking the lives of unarmed passengers, as with the Lusitania ship, which 120 American died. The Germans were asked to stop the attacks but they did not and many US ships sank, shedding off US citizens lives. The submarine warfare enraged the US neutrality which then turned against the German and declared war on March 1 in 1917.

the answer that best explains what happened to george washington at fort necessity, pennsylvania is : washington was attacked by the french but was able to negotiate with them to peacefully end fighting. the battle took place on july 3, 1754. the battle is considered as being the start of the french and indian war.

the china one is last

explanation: