Ben Frumin May 5, 2010, 5:37 PM

Sen. Joe Lieberman (I-CT) is not backing down. Americans who side with terrorists, he says, should lose their citizenship.

Lieberman has been making waves for the last day or so over his proposal to revoke the citizenship of Americans who become terrorists. Lieberman’s push comes on the heels of naturalized American citizen Faisal Shahzad being charged in Saturday’s failed Times Square car bomb attempt.

“If you’re attacking your fellow Americans in an act of war you lose the rights that come with citizenship,” Lieberman said yesterday.

And today, the senator from Connecticut isn’t backing down.

“If an American citizen like Shahzad is shown to have joined and worked with a foreign terrorist organization whose aim is to attack Americans, kill Americans, I don’t think it makes any sense to continue to give them the privileges of American citizenship,” Lieberman said on Fox News.

Lieberman said he’s merely suggesting that the U.S. update a decades-old statute that calls for Americans who join foreign armies fighting the U.S. to lose their citizenship.

The senator said there’s a process involved in this de-citizenizing — complete with an initial State Department decision and appeals process.

“This is not gonna just be Joe Lieberman in a room somewhere saying, ‘Ah, you’re an enemy of the United States, you lose your citizenship.’”

This is not a major step, it’s just updating a law that exists and it’s doing what’s right. American citizenship is a privilege, not a right.

Lieberman will officially roll out the “Terrorist Expatriation Act” at noon Thursday with Sen. Scott Brown (R-MA) and Reps. Charlie Dent (R-PA) and Jason Altmire (D-PA)

When Lieberman proposed the idea yesterday, it wasn’t clear whether the revocations might apply to groups like the Hutaree, a Michigan militia that planned to target the government. Though Lieberman didn’t address that concern specifically today, he did say the rule would only apply to Americans who “join a foreign terrorist organization as designated by the U.S. Department of State.”

Yesterday, it also seemed like Lieberman’s proposal had the support of Sen. Chuck Schumer (D-NY), who told AFP: “That sounds like something I’d support, but I’d have to look at the legislation.”

But today, Schumer’s spokesman tells Greg Sargent:

The senator was approached abruptly in the hall of the Capitol by a reporter before he had even heard about the legislation or what it did. Having learned about the proposal, he believes it would be found unconstitutional in this context and would also be ineffective. There are much better ways of obtaining information from terrorists.

Citizenship, Faisal Shahzad, Joe Lieberman