Answer:
Germany sent a coded message (aka Zimmerman Telegram) to Mexico proposing an alliance between Germany and Mexico. Germany suggested Mexico reclaim it's former territory by going to war with the United States, thus distracting them from the World War. President of the United States Woodrow Wilson got his hands on this telegram and joined the Triple Entente in the war weeks later.
Explanation:
Samoa was a stopping point for the US Merchants.
Gravity. Gravity was a theory crafted by man
Expences from the french-indian war. the british had a lot of dept and were using the americans to pay for it
They relied heavily on trade