Their eccentric elements notwithstanding, the Tea Parties have something vital to offer the country: a vocal, activist constituency for spending cuts at a time when politicians desperately need to have their spines stiffened on the issue. But it’s all too easy to imagine the movement (which, after all, includes a lot of Social Security and Medicare recipients!) being seduced with rhetorical nods to the Constitution, and general promises of spending discipline that never get specific.

It wouldn’t be the first time a mass protest movement won a rhetorical victory without achieving a lasting policy shift. The antiwar movement, for instance, seemed to effectively take over the Democratic Party in the middle years of the Bush administration. But here we are, two years into a Democratic presidency, and Gitmo is still open, the U.S. is still in Iraq, and Barack Obama has escalated the war in Afghanistan.