What is supposed to be the first war America waged on foreign country?

[I Am Feeblepizza.]

I believe that the correct answer is the "Quasi War" with France during the late 1790s. I wouldn't count Indian nations as foreign countries because they existed entirely within the confines of the European colonies and weren't really recognized as actual nations anyway.

[I Am Feeblepizza.]

So, depending on how one defines the various terms, the answers are:
1.The "Quasi War" with the French (wasn't really a war)
2.The fights with the pirates (were wars, but were defensive in nature)
3.The Indian Wars (were not really "foreign")
4.The Mexican-American War

Somebody answered with the Spanish-American War as well.

[I Am Feeblepizza.]

The Mexican-American War happened first and met all the possible definitions.

If the "Quasi War" and the Indian Wars don't count, then the one that happened first would be the Barbary Wars (the fights with the pirates).

[I Am Feeblepizza.]

because they existed entirely within the confines of the European colonies

Not from their point of view.

That doesn't change the fact that, in reality, they did.