Where do non-Americans get the moral authority to judge the United States?

There is no moral high ground other nations can stand on in which to condemn us in the United States. Especially in Europe ! It seems today that Europeans like many Americans lack a sense of history. It seems that they have forgotten what an imperialistic America did at the expense of hundreds of thousands of its lives. Liberate and free an oppressed continent from fascism. Whats even more saddening is to see Americans cast such a disparaging image on the very country who's sacrifices have allotted them to do so. What I've always wondered is how anyone who claims to love freedom and who desires the chance to seek their own fortune in an enviroment that has no limits to acheivment could chastise America.