I was also taught these things in the south, living in North Florida. As part of a 1 semester Florida history class in middle school, we also went into each of the spanish conquistadors and how they murdered their way across the continent.

My AP history teacher gave us copies of Zinn's A People's History of the United States as a supplemental to our textbooks. She was an awful teacher overall, but I appreciated her trying to make sure we had multiple perspectives.

Then I went to an elite east-coast private college, where I almost failed US History because I called the professor out for teaching Lost Cause bullshit.

Yeah we talked about colonialism in my middle school.

However, it was discussed as a fact of history and we went into detail about the slave trade triangle and all that.

And we did it without politicizing it. It was facts-based rather than pushing some weird political narrative about how america is heroic, or america is evil. Fancy that... just teaching history.

But the way they teach it in school

Nah, I was taught the latter way in school. They pretty explicitly told us about the 3/5 compromise, the lack of voting rights for women, etc. Really, its pretty hard to avoid the idea that all people were not seen as equal in the eyes of the constitution when ratified, when you know that we have a whole unit on the civil war coming up.

it was an aspiration, a goal of our forefathers.

I just do not believe this. These are people who regularly raped their slaves, and then enslaved the progeny.

it was founded on the principles of liberty and equality for all.

No. Not at all. Give me a break. No women, natives, enslaved people, etc.