I guess Germany and England were arguing about South American, then the Germans sank the Lusitania in 11/14. The US policy was to stay out of it until Germany appeared to be on the verge of victory.
---From the book Don't Tread On Me by H.W. Crocker III
Chancellor Georg Hertling stated: "At the beginning of July, 1918, I was convinced...that before the 1st of Sept. our adversairies would send us peace proposals...We expected grave events in Paris for the end of July. That was on the 15th. On the 18th even the most optimistic of us knew that all was lost. The history of the world was played out in 3 days."
The German army had eviscerated Russia. It had crumpled Serbia, Romania, and Italy. It had demoralized the armies of France. And yet, on the western front--now the decisive front--the bulldog British and the hard charging Americans held the line and then advanced, shifting the tide so that imminent German domination of the European continent became imminent German defeat."
The book goes into great detail about the battles.