A nation's flag is its symbol of unity.
I think that when you make a big deal out of burning a flag, in public, you show a blatant disrespect for the people of that nation.
Having said that, however, I don't think it should be a 'punishable' offense.
Here, in Australia, people burn flags left, right, and centre--they quite literally use it as a protest against all sides of the government. The majority of us, don't like it, but I've never heard of anyone actually being prosecuted for doing it. I mean, what would be the point? It would simply give more publicity to what ever cause was being protested by the flag burners in the first place.
And, no I don't think it's every person's right.