In an afterword appended to the White House diaries he published this week, former President Carter muses, “It may be difficult for some younger readers to realize how much the Washington political scene has changed in the last 30 years.”

Carter points out that the congressional bipartisanship on which he relied for his considerable number of legislative achievements no longer exists and that the “pernicious effects of partisanship have not been limited to Washington; American citizens have also become more polarized in their beliefs.... Almost all segments of American society — the poor, the middle class and the wealthy — have become more alienated from our government. Observing the behavior of the Washington political establishment, people too often feel only frustration and mistrust; inevitably, we now see frequent exhibitions of anger and vituperation.”

It’s impossible to quarrel with Carter’s characterization, and equally impossible not to notice that in an era when people speak only to those who share their particular angry haze, the politics of delusion and self-deception flourish. Take the current midterm election campaign, in which it has become commonplace for Republican/"tea” party candidates — the two names now are interchangeable — to assail President Obama’s alleged radicalism and his purported plan to transform the United States into a European-style social democracy.

Putting aside the nonsensical nature of these claims, what’s startling is the unchallenged way in which they rhetorically invert the factual geography of the electoral landscape. In fact, it’s been more than a century since a viable party has nominated as many candidates with such radical views for federal office as the Republican/tea party has this year.

Writing in Tuesday’s Wall Street Journal, Mississippi Gov. Haley Barbour, chairman of the Republican Governors Assn., said that electorally speaking, you now can “replace ‘Tea Party’ with ‘Republican’ ... and each description would remain totally accurate.” The voters who support the GOP/tea party, he wrote, “fear that their children and grandchildren won’t inherit the same country they inherited from their parents and grandparents.”

The irony here is that electing the candidates Barbour hails will guarantee that the children will inherit a country their great-grandparents overwhelmingly rejected — one that existed in Herbert Hoover’s era or, in some cases, before the Civil War. In fact, none of the five Republican presidents who’ve held office since the Depression have advanced anything like the current GOP/tea party’s radical agenda.

It’s hard to tell exactly what Christine O’Donnell, the Republican nominee for a Senate seat in Delaware, believes, though we do know that she’s dabbled in witchcraft, doesn’t pay her bills and thinks scientists are breeding mice with human brains. In Kentucky, senatorial candidate Rand Paul wants to eliminate the departments of Education and Energy, as does Alaskan nominee Joe Miller, who also says that unemployment insurance is unconstitutional. In Utah, GOP Senate hopeful Mike Lee wants to repeal or amend the 14th and 17th Amendments, thereby doing away with our current citizenship laws and the popular election of U.S. senators. Sharron Angle in Nevada has ruminated about abolishing both Social Security and Medicare.

There’s actually less difference than one might think between the views of these tea party “insurgents” and those of establishment Republicans. If, as now seems possible, the Republicans recapture the House, two incumbent congressmen with an outsized say on budgetary policies will be Wisconsin’s Paul D. Ryan and Virginia’s Eric Cantor. Both already have signed off on a plan to privatize Social Security and to replace Medicare with a vague voucher system. Meanwhile, former Republican House Majority Leader Dick Armey denounces Social Security as a fraud and a Ponzi scheme.

Sen. James M. Inhofe of Oklahoma, who would replace Barbara Boxer as chairman of the Committee on Environment and Public Works if the GOP recaptures the Senate, believes that global warming is “the greatest hoax ever perpetrated on the American people.” Then there’s presidential hopeful Newt Gingrich, who fulminated darkly about anti-Christian liberal plots and wants to pass laws banning the imposition of Sharia law. (We’re all losing sleep over that prospect.)

Picture for a second an America without Social Security, Medicare or unemployment insurance. Imagine this country without the 14th or 17th Amendments or effective federal oversight of education or energy.

The rude beast of radicalism may be slouching toward the polls in November, but it didn’t start out from the White House.

timothy.rutten@latimes.com