Sinking merchant ships.
The Germans then threatened to use only Uboats for war and blew up a few ships.
because of the alliances the US had made previous to the start of the war along with the threat of the German Uboats attacking US civilians and property.
300,020 airplanes where used in World War 1
Yes it was used in World War 1 but it was stopped being used in World War 2
Yes, world war 1 had tanks. World War 1 was the introduction of battle-ready tanks used in war.
Mainly horses were used in World War 2. But donkeys were used in World War 1.
Dynamite was used in World War 1, but stopped using it during World War 2
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.
Dynamite was used in World War 1, but stopped using it during World War 2
it was never used in world war 1
world war 1 money
Nuclear bomb.