Hello knzhou,
I think what you describe is a very interesting experience.
I'm not an American, but I lived there for many years as a young adult, and I now live in Australia.
One thing both our countries have in common is that we both lock children in cages - refugee children - and we pay private contractors to do it in out of the way places - and extraordinary lengths are taken to avoid public oversight.
Terrible things happen in both countries, and overseas on behalf of both countries.
Currently a prominent former Australian solider appears to be under investigation for kicking civilians of a cliff (to their death) in Afghanistan because it was inconvenient to keep them prisoner. I say _appears_ because there is a lot of secrecy around the case.
Being challenged on the the ugliest truths about our nation or group is difficult, and it is rarely done in a way that is an example of elevated standard of generous and noble behaviour the speaker suggests we should be held to - If there is a European country that is an example unbroken principled dignified conduct I would be delighted to learn of it's existence.
That said, the anger at the hypocrisy of the person challenging us, is probably best separated from the shame we feel at the truth about the darkest sides of our nations.
Everything that is good and true about the United States and Australia as immigrant nations that allowed people fleeing poverty and war a new and better life, is not invalidated by, nor does it invalidate the reality that both nations were built on a genocide of the original inhabitants, that slavery and oppression were used to build the foundation of the wealth we now enjoy.
I think we are a better kind of patriot, when we see the horrors of our own countries and do no look away or excuse them, and we are even better when we work to fix the parts of our nations that are broken.
I've always felt the phrase 'my country, right or wrong', is a more noble statement if is taken to mean I take responsibility 'right or wrong' rather than the double speak interpretation of "right even when it's wrong".
If you are anything like me, then probably both of us are guilty of not being patriotic enough, of enjoying the privileges and wealth our nations provide and taking too little responsibility for helping steer its course.