It's one thing to be Republican and another to call him a "domestic enemy'. That phrase is very deliberately chosen to inflame sentiments in the Armed Forces over protecting the Constitution from "enemies foreign and domestic", which is a phrase in the oath taken by U.S. soldiers upon enlistment. It's the same one I took when I joined the Navy, even if they didn't want me in the end, and it is a powerful experience. It is intended to create an atmosphere in which military violence against Obama can be justified, at least in its most extreme forms. I certainly have feelings myself that, having taken the oath to defend the country and not particularly thinking Obama is a goddamned liberal faggot traitor as so many of the angry right-wing protesters do, I may have some sort of duty to try to protect the country from them - though, of course, not being in the military myself anymore, all I can do is try to speak out against it in the civilian sector.
We have a black President in office who already faces a tremendous degree of danger due to his skin color. For Chuck to join in this "domestic enemy" rhetoric is dangerous and ridiculously irresponsible. I took classes in his "system" of martial arts when I was a kid. They were a joke and then the instructor scammed a bunch of parents including mine and then closed the school and left the state...nobody blamed Chuck, but the karate was still crap.
I joined in the Internet memes because they were fun, but the reality of it is that Chuck's getting to be an old man and lots of people out there could pretty easily beat his stupid wrinked grizzled ass at this point. And if he actually uses any kind of EXPLICIT language to incite violent sentiment against Obama, perhaps they ought to.