You just didn't understand the answer and never will. There is more liberty and justice for all in America than there has been anywhere in the world at any time. If you are a white, and this applied to women, as well as men, what you write is unquestionably true with regard to liberty. The ability to move around without having to carry a government-issued ID, to drive a new or fairly new car without any license plates, to register into a hotel or motel under another name and not be asked for an ID or a passport I have found in no other country. If you are black or brown, however, none of the above are true.
Justice is quite another thing.
As I and others have pointed out, black men and youth go to prison for crimes for which white men and youth receive probation and counseling. Black, brown and other minorities are not leaving. It's because they realize they are better off here and have more rights here. You say that from the position of a privileged white male. I would be more impressed if you would cite a black authority for such a statement, apart from your good buddies, I presume, Tom Sowell and Ward Connelly.