Yes, Americans are pround of it.

Regarding some disputing example in your post, I can mention similar thing too. For example, in any US airport you can not in any way say or hint that you have bomb. You would be subdued if you say so. It does not voilate your 1st amendment right, however.

You extended the concept of free speech and press to the extreme. Please read the 1st Amendment in legal sense.

Democracy and freedom has other thing that are often forgotten by people. That is law and order. The "law" are the rules set and agreed upon through democratic process participated by concerned people. If majority of Americans think burning flag should be legislated as illegal, Congress will honor the will and make such law. It does not voilate people's 1st Amendement right.

So the key thing here is Amercian people. It is they who will decide important thing like this. The way they do it is through their democratic process like periodic elections of official to executive and legisture

Democracy, Freedom and rights and a lot of things have been widely known American greatest contribution to world civilization. It has boomed in almost every corner of the world since WWII. You will be surprised how many countries constitutions quote from American Constitution,including Chinese.

If China would like to replace USA in next centrury, they must come up with something better than what USA offered to the world in 20th century, not just GDP. I do not know what China can offer now. I know for sure that "3 represents" is not working for sure. They need something better, much better.