I begrudgingly love the US and the idea that anyone from anywhere can be an American. America takes in more refugees than the rest of the world combined, and the majority of Americans today, including myself, are descended from at least a few. The whole population itself is descended from immigrants who mostly came in the last century, which instills a sense of shared nationalism not based on ethnicity or race but on the ideaology of democracy and individual rights. The vast majority of even the far rightwing nationalists are in support of some consistent immigration. From what I have heard the US is also better at assimilating immigrants both culutrally and economically than many European, African, or Asian nations.
Having said this, the government itself is often paralyzed, and despite having such great wealth and power, individuals within government and industry on both sides often make a concious decision to abandon the well being of the poor and working class. It isn't about capitalism vs. communism as some make it out to be, but on whether the government is willing to provide basic affordable healthcare and affordable shelter to those in need.
Large corporations held by a few wealthy individuals and families have held quasi-control over the government through legalized bribery for decades. Likeweise most mainstream media corporations are owned and controlled by a small number of individuals. The wealthy are able to both subvert the rule of law and manipulate it against others without consequence, all the while wealth inequality is rapidly increasing. It doesn't help that many wealthy people try to pay less in taxes than a minimum wage worker. If the rule of law can be bent openly the perception of the law as infalliable will continue to go down the drain as more and more people begin to question the legitimacy of the government itself.
There is also at times a lack of any sense of community. Many people don't feel like they have any stake in society in general and therefore feel less obligated to contribute to the collective. If you are disconnected and disaffected by those around you and you feel no pride in any organization (like your nation) the only thing that gives life meaning is generating more wealth for your own personal enjoyment. This loss of community is weaponized on both the left as a symptom of late stage capitalism and shitty urban planning and on the right as a loss of national identity and culture, but neither side acts with any efficiency to fix it.
Another problem is that with increased polarization, personal ideas of what defines "America" are starting to diverge too rapidly, leading to occasional violence. Mass shootings (like 20+ people) perpetrated by a societal outcast or a frustrated student have been happening every few years for my whole life, but politically motivated shootings are (although usually more like 5-10 people) becoming more common than they used to be, which should be mildly concerning imo.
Although I just wasted 10 minutes of my life typing some complaints instead of actually doing something productive with my life so yknow maybe I am the problem here. I don't believe in the "USA is the greatest nation to have ever existed on the planet so you're not allowed to have an opinion" line but its true that materialistically life for many is significantly better here than in much of the world.