Much of the East coast was blacked out as Nazi Uboats were sinking shipping all the way from NY to FL. They also did some shelling with their small deck guns.
Wilson entered WWI because the German Uboats were destroying Americas ships. Also the Germans sent the Zimmerman letter to Mexico to ask them to join the war. If they won Mexico would receive all the land in America.
Who all ever was involved in the war.
All participants, on all sides, used biplanes.
World War I was the bloodiest war of World War I as it was the only war of World War I. The same can be said of every war.
All the governments used propaganda.
Rifles.
Rifles.
All countries fighting in World War 2 used weapons.
All sides in WW1 used artillery.
The Great War War to end all wars
They all did.