Honestly that's something I never learned about until I was like, 23, 24. Still know bugger all about it and that's fucked. Do you know any good resources where I can learn about this stuff?
Wilson, and to a lesser extent Monroe are the presidents that caused those, with Wilsonian Military Doctrine, and The Monroe Doctrine, specifically so perhaps start there.
For a fun and light read I'd start with Wikipedia entry on the attempts on the life of Fidel Castro.
For chronological read I'd start with Iran then Latin America, Wikipedia as well. Don't skip the chapter where they associated themselves with drug lords that sent drugs to US as a way to finance anti communist operations in Central America. I think that was Nicaragua.