LAD 10

The monroed doctrine said that European powers could no longer have claims to land in the americas. This expressed american nationalism, and the new feeling of global power that we were starting to have post 1812 becuase we were able to stand up to european powers that were much stronger. Also it was showing how we wished to remain neutral.
Adams would have wrote the Monroe doctrine, becuase jefferson and madison were telling Monroe to ally with France and Britain in order to keep spain from reclaiming their colonies in the Americas. Adams wanted the US to have more control in the Americas, and not have to worry about European affairs, so he wrote the Monroe Doctrine to keep all Europeans out of the Americas, even though they were not strong enough to enforce it.
The most important part of the Monroe Doctrine was Adams stressing the importance of neutrality for the nation. Without it, there would have been many more wars in America's early years against more powerful countries, and the US would have had a hard time growing.

In the Cuban Missile Crisis, the US was very worried about another world power's.
presence in the Americas.