The obvious reason why the rightwing of this country would openly embrace McCarthyism now is obvious -- it is because McCarthyism parallels and supports the Bush administration's policies regarding the War on Terrorism.
It's their way of indicating that they think that spying on our own people, targetting Arab organizations, and targeting those who oppose war is the right thing to do, as there are terrorists out there. They want a new witch hunt, even if those whose freedoms are violated almost invariably aren't the witches themselves.
This offends me deeply. It should offend any American. I would say that there should be laws against what we're doing in the name of this War on Terror, if there weren't already laws against it. A lot of what we are doing is in violation of the Bill of Rights and the Constitution, after all... so why do we make it so easy for our leaders to play games and dismiss our most fundamental rights as a nation? It's really, really easy to give away a right, but it's very hard to get it back again. Why, in the name of freedom, have we embarked upon a course of paranoia, blind hatred, and national hysteria?
Those who forget the past are condemned to repeat it, I guess...