Madison's and Jefferson's concern for our flag was not about material property issues.
They both believed that the physical integrity of the flag was necessary to the sovereignty of our country. And although both were involved in international legal actions regarding the flag, neither expressed any belief that physical insults to any nation's flag could be construed as freedom of expression.
To begin research into the truth about what our forefathers thought of flag desecration, start with Endecott's Case in Massachusetts.
Go from there, then find the case of the first US flag burning that the hippified (during that time) members of the Supreme Court supported.
It's a study in the very recent degradation and weakening of our country by people who think only of themselves against what our soldiers and other defenders have given for them.
I continue to disagree with you. Even if a founding father here or there said that a particular flag ought to be protected, I have my own reasons for opposing this amendment. I respect the military's own esprit de corps, but civilians have their own ideas. The military is not free to impose its own standards on civilians. As I have said, I have spoken at length with a very wise and well-thought veteran who nearly died for this country one day about 60 years ago. He instilled in me a great respect for the flag, and I've never known anyone who cares for it better. But he explained that one of the freedoms for which he fought and nearly died was for a flag owner to desecrate his own flag for his own reasons. You are afraid of something, and that is why you want an amendment. I do not share those fears, and neither did the patriot of whom I speak. He did fear people who would run scared while making legislation, however. That is when our freedoms are most at risk.