For all my life, the rightwing in this country has called any questioning of their beliefs, tactics, leaders, or even lies "UnAmerican." Told those of us against Nuclear war to go to Russia, those of us for Civil Rights for "blacks" to go to Africa. Those who questioned the Bush/Cheney claims about Iraq's "Weapons of mass destruction" not just "UnAmerican" but "traitors" and usually everyone, almost, in the media and Congress and elsewhere fell into line, afraid of the accusation.
Now someone's calling them "UnAmerican" and it makes them very angry. If only it would give them some insight into their own past behavior. But I doubt it. See the troll's comments lately on this blog for evidence of their ideological intransigence in the face of reality. Does anyone truly believe that Palin truly believes that Obama is out to murder her Down syndrome child and her parents through healthcare reform as she wrote on her Facebook page recently!?