The correct answer is that the bombing of Pearl Harbor in 1941 by Japan made American isolationists quickly change their tune as America was under attack. Once Germany declared war on the US, the US was fully into the war.
They were pretty mad that they got kicked off of their land, we took their land because there was gold there and we made them walk on the trail of tears
I think it's war but I'm not really 100% sure on it
I think it's the telephone because it allows people to communicate better and customers or workers don't have to walk up to everyone and disturb them. You may elaborate more on this with your own opinion
