While I agree with you wholeheartedly, the imperialistic legacy is broader and includes a nearly contiguous history of wars:

https://en.m.wikipedia.org/wiki/List_of_wars_involving_the_United_States

Even Obama continued the War in Afghanistan while lying to the American people about US casualties.

Clinton presided (along with allies) was involved in 5 wars during his presidency, two of which were to stop genocide.

Kennedy/Johnson were responsible for beginning and escalating the war in Vietnam.

With the exception of Teddy Roosevelt and Wilson, all the other Presidents were Republicans.

The real crux of American Imperialism has been a legacy of protecting and secure assets for American based business interests overseas. Continuous growth is built into American policy beginning with the founders in 1776. Growth and money and I don't see that changing any time soon.

For more - look at any Noam Chomsky interview on You Tube.