Rick Perlstein argues that the Tea Party movement is simply the latest iteration of a common phenomenon:

As the Times’ new poll numbers amply confirm — especially the ones establishing that the Tea Partiers are overwhelming Republican or right-of-Republican — they are the same angry, ill-informed, overwhelmingly white, crypto-corporate paranoiacs that accompany every ascendancy of liberalism within U.S. government.
“When was the last time you saw such a spontaneous eruption of conservative grassroots anger, coast to coast?” asked the professional conservative L. Brent Bozell III recently. The answer, of course, is: in 1993. And 1977. And 1961. And many more.

Consider (per TPM) this video of Victoria Jackson -- yes, the former SNL star; she's a certified right-wing loon -- performing "There's a Communist Living In The White House" before a rapt Tea Party audience in Washington today:

Some of Jackson's reasoning is literally identical to the reasoning of Cold War right-wing paranoids -- President Obama had Marxist professors, therefore he is a Marxist. Some if it is parallel though different in detail -- Jackson claims that the health care bill would mean that the government decides if you can get chemotherapy, that Obama plans to close down talk radio, and other wild claims. Nothing specifically about floride in the water supply but the style is identical.