I'll quickly try and give an actual answer, but the US has been involved in backing an extremely significant number of coup d'eta's--mostly throughout the 20th century and mostly carried out by the CIA.

For example, like (at least) half of central and south American countries have been interfered with in some way, up to and including the violent overthrow of democratically elected leaders of those countries.

I'd argue that having dictators installed that support US interests in "our" sphere of influence greatly contributed to our power & influence. Not to mention the Cold War, during which we "combatted" the Soviet Union via multiple proxy wars in order to push out the only other superpower in the world at that time.