Because of the threat of the Soviet Union.
The United States believed the war posed a threat to world oil supplies
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.
Cuba was an ally to the US during World War II. But after the war, Cuba became communist and joined on the side of Russia against US. Cuba and Russia were also launched the nuclear threat on the US and Mexico.
Because of the growing Japanese threat Pearl Harbor and the Blitz
No, America was not involved in the war until the enemy became a threat to them. they joined the war of world war 1 late and then kicked their asses. same with WW2 The US joined the Allies in April 1917 in WW1.
I honestly dont know. We will do further research into the topic. ;)
None, in fact US seems be threat to the world.
The threat of communism - APEX
When Napoleon sold the Louisiana Territory to the US in 1803, it was a sign that he had no ill intentions against the US. He made the deal to keep Great Britain from taking New Orleans. Great Britain remained a threat to the US as the War of 1812 pointed out. Also, world politics do change and in 1860, France would make a play in Mexico. This would be a threat to the US. In summary, the Louisiana Purchase did not prevent the US from having a war with a European Power.
When Napoleon sold the Louisiana Territory to the US in 1803, it was a sign that he had no ill intentions against the US. He made the deal to keep Great Britain from taking New Orleans. Great Britain remained a threat to the US as the War of 1812 pointed out. Also, world politics do change and in 1860, France would make a play in Mexico. This would be a threat to the US. In summary, the Louisiana Purchase did not prevent the US from having a war with a European Power.
When Napoleon sold the Louisiana Territory to the US in 1803, it was a sign that he had no ill intentions against the US. He made the deal to keep Great Britain from taking New Orleans. Great Britain remained a threat to the US as the War of 1812 pointed out. Also, world politics do change and in 1860, France would make a play in Mexico. This would be a threat to the US. In summary, the Louisiana Purchase did not prevent the US from having a war with a European Power.