At 54 years of age, I have seen just about every type of political activity there is. I personally saw the US flag being burned by anti war protestors during Vietnam. I saw our flag being dragged in the mud my Iranian "students" in 1979. At one time I saw a prade through downtown Seattle protesting the showing of a Nazi anti jew propaganda movie (circa 1936) at a movie house that showed historical films. At the end of the parade they burned the US flag.
Maybe I'm somekind of right wing emotional dum-dum the left wing liberals would have us believe, but isn't the flag the symbol of the United States (i.e. the constitution)? And doesn't that document give us all the right of freedom of speech?
As I see all of this, dissent is not a right in a democracy like ours, it is an obligation. Without letting our elected officials know we disagree with them, we will abrogate our freedoms. At the same time, we need to protect the rights of those we disagree with. 'I may not agree with what you say, but I will defend to the death your right to say it.' Voltare