Does treason really mean anything anymore?

Eugene Volokh addressed the issue of whether statements like George Galloway's (comparing Baghdad and Jerusalem to two beautiful daughters of the Arabs who are being raped by Israel and the U.S.) could be the basis for treason charges.

Tony Blair has proposed measures to deport or denaturalize Muslim radicals who encourage, advocate, or glorify terrorism. Some American intellectuals are alarmed by the implications of such a policy for freedom of speech.Glenn Reynolds, however, isn't so sure:

It seems reasonable to me that those seeking asylum should be required to show some loyalty to the country they're seeking refuge in. And it seems reasonable to me that the civilized world ought to be taking action against those who agitate on behalf of terror, regardless of whether it is done through treason prosecutions or other means.

Me too. There is nothing in the Constitution that requires us to take vipers to our bosoms who go beyond dissent and foment murders.