Glenn Beck admits he shares Joseph Stack's dislike for the IRS and taxes, but he denies you could lump Stack in either with the left or the right.

We have no idea what this man's ideology is. He could be from the left, he hates capitalism. He's got an anti-business rant that goes on and on and on. It sounds like anything you would hear at a speech from Van Jones. When you reach his anti-tax ravings, and his anti-tax or IRS stuff, he sounds like, you know, you could be reading bumper sticker off the car of the signs at a tea party.
Most importantly, Beck says it "doesn't matter" what politics Stack shared because "the guy is a killer." Speaking directly to people on the Web who have been cheering Stack's IRS attack, Beck says:
Do not become like these people.  We're not these people.  These people kill innocent people.