From last year: author John Scalzi deftly demonstrates why any Constitutional amendment allowing Congress to ban burning of the United States Flag will only make the people behind it look incredibly, incredibly stupid:

"Protecting" the flag with a Constitutional Amendment won't solve the not-at-all pressing problem of people burning flags for political protest. They'll still do it. They'll simply do it in ways that will now additionally mock the stupidity of those who love the symbol of American freedoms more than they love actual American freedoms. And no matter how expansively Congress defines "the American Flag" there will always be something that is not the flag, but is close enough in its shape and structure to feel just like the flag. And there will be the people who will use that not-quite-flag-like object to protest.

And you know what? Good for them. They're being better Americans than those who would pass a flag-burning Amendment. Real Americans don't take away the freedoms of other Americans.

I agree with one of Scalzi's commenters - I want that last sentence on a bumper sticker.