Nonsense. The law ALSO allows you to employ reasonable force to protect property, it's just circumscribed to a greater degree. For example, in most jurisdictions you cannot use deadly force to protect property (but don't try to burgle a Texan's home). I'm sorry if you don't like that, but it's the law.
Things tend to sort themselves out when both sides are allowed to express themselves freely. In your example the second veteran would not be privileged unless the first veteran were employing unreasonable force on the flag burner. The second veteran could and should be prosecuted for assault.
Abortion clinics are private property. They don't factor into the discussion.
This isn't rocket science. Scenarios such as these are being played out every day under the law in countless venues. All I'm suggesting is that we place public flag desecration on the same level. The government should butt out and let people sort it out.
Sure, your own property. If I burn your flag, you can stop me. If I burn my own flag, you have no right to interfere with my destruction of my own property.
So, if I walk into a store and purchase a flag, that's not private property?
And a flag isn't? If I go out to Wal-Mart and buy a flag with my hard-earned paycheck and then burn it on my lawn, seems like it's all private property to me.
You're right; it isn't rocket science: you can't attack people for engaging in speech you don't like. You just can't. End of discussion. It doesn't occur in a civilized society.