You can legally treat your copy any way you want; just dont violate anyone elses rights in the process. And don't violate laws against fires on public property.
The Constitution doesnt contain any right against seeing someone mistreat their own property. Your outrage at such an act is legal, but doesnt permit you to physically attack a person or otherwise violate their rights.
But you are always free to peacefully express an opposing viewpoint. And alert the police to any violations of public safety or anti-burning laws.
.
What the Hell are you talking about? I didn't mention any violence.