I believe it was governor John M. Slanton who sentenced Leo Frank to death.
Answer:
its either Boston, New York or Philadelphia
In short, Germany was close to being defeated, and America wanted to be part of the post war carve up (when territory was divided). The US was supplying war materials to the Allies and could not do so while maintaining complete neutrality. There was also the sinking of the British ship Lusitania which angered the US. Also, the Zimmerman telegram.
According to my data it will be the first one