Mexico, Puerto Rico, Samoa, Hawaii, Guam, Cuba, Panama, and the Philippines?
In the last 100 years the trend has been been for America to invade a country and try to install a friendly government rather than formally annex them - Vietnam, Korea, Iraq, Afghanistan, Libya, Yemen, Syria.
Oh plus all the overseas military bases: https://en.wikipedia.org/wiki/List_of_countries_with_oversea...