I had to wince when I saw poor old John McCain last week, standing on stage with a constipated smile as his former running mate Sarah Palin threw him a bone.

It was a cringe-worthy sight. McCain is a true servant of his country, a former POW and presidential candidate. He is one of those people who has to qualify for the title of Great American.

And yet there he was, with that frozen rictus of a grin, silently begging to keep his job, as the woman he once plucked from obscurity magnanimously asked the crowd of Arizona Republicans to help him out.

About the same time as McCain was facing his antagonists, David Frum was being fired by the American Enterprise Institute, the conservative think-tank in Washington where he'd opined from the political right for years.

Arizona senator John McCain greets his former running mate, Sara Palin, during a rally in Mesa, Ariz., in March 2010. It was only their second rally together since losing the presidential election in November 2008. (Matt York/Associated Press)

Frum, George W. Bush's former speechwriter, and McCain have a few things in common.

Both are more interested in fiscal and national security issues than in gay marriage or abortion or prayer in schools; and both tend to shun demagoguery for rational debate, which nowadays makes any Republican a candidate for the Tea Party's rub-out list.

McCain is the man who reached across the aisle to draft a bill outlawing the Bush administration's torture of Islamist detainees. No puzzle in that: His own courage under torture at the hands of the North Vietnamese has become an American fable.

He has also co-operated with Senate Democrats to create a path to citizenship for the 11 million or so illegal aliens in the U.S., the invisible, cheap-labour underclass that everyone knows is here to stay.

Further, he stubbornly resisted Bush's tax cuts, saying America needed to pay its bills.

In 2008, those and other policy stands gave him maverick status — and his party's presidential nomination.

These days, however, McCain's history has made him a target of the ultra-right Tea Partiers, who view him as a pro-tax, pro-illegal-immigrant, pro-terrorist appeaser.

They may well see to it that he will lose his party's Senate nomination this year to J.D. Hayworth, a conservative talk-radio loudmouth who once said that legalizing same-sex marriage could lead to humans marrying horses.

Losing their marbles

Frum's attempt to speak common sense to the party he supports put him in pretty much the same position as McCain.

He called the Republican's absolute-obstruction strategy on health-care reform "disastrous," arguing it cost conservatives the chance to participate in governing.

Barack Obama, Frum pointed out, was elected with a strong majority and any talk of repealing these health-care reforms is deluded.

Entitlements like health care are instantly addictive, which means the law is here to stay, Frum argued.

"We went for all the marbles," he wrote in his column. "We ended with none."

Where to hide?

That sort of language, of course, just gets the Tea Partiers angrier. And when they are angry, they frighten the Republican elite, including, apparently, Frum's boss at AEI.

With their confusingly contradictory demands, their goon tactics, and their ability to organize and channel spluttering visceral fury, they are truly the loose cannon of American politics, endangering any conservative politician who doesn't either ride with them or hide from them.

A Tea Party rally in the desert outside Searchlight, Nev., in March 2010. (Isaac Brekken/Associated Press)

During the health-care vote last week, Tea Partiers behaved like the snarling white mobs that lined the streets of Selma, Alabama, 46 years ago.

They surrounded representatives John Lewis and Emanuel Cleaver, both civil rights legends from that era, as they entered the House to vote.

One protester spat in Lewis's face. Another called Cleaver a "nigger." This, in the shadow of the U.S. Capitol in 2010.

When Barney Frank, the openly gay congressman from Massachusetts, arrived on the Hill with his partner, he was mobbed, too. "Faggot," someone yelled.

Inside the House, one protester made it into the public gallery where he began screaming curses and insults. Republican lawmakers applauded him, even as police struggled to haul him away.

There were several explanations put forward for the behaviour, but Fox News Channel's Glenn Beck, a Tea Party hero, provided the richest one: The Democratic lawmakers, he said, had deliberately provoked the crowd by walking around the grounds of the legislature in which they serve.

Why trust facts?

Now, everyone knows the Tea Partiers hardly represent mainstream American voters, or even mainstream conservatives. But they do yell loudest and grab the most microphones, so even John McCain (who would never, incidentally, applaud a screeching, cursing protester), has gone to them as a supplicant, cap in hand.

That's what the Palin's for-old-time's-sake endorsement at the rally was all about, although it's uncertain even that will save him.

But even those politicians who embrace the Tea Partiers must realize that there is, in the end, no way to make them happy. They run on adrenaline and resentment, not logic.

Indeed, several of the movement's leaders are unemployed, having lost their jobs to the recession. Some are collecting federal jobless benefits. Others are collecting social security. The older ones are enjoying government Medicare.

And yet they inveigh against the growth of government — precisely the sort of growth that took place most vigorously under George W. Bush. These are people with no sense of irony.

One Tea Partier, having had those incongruities pointed out to him by a reporter recently, replied "If you don't trust the mindset or the value system of the people running the system, you can't even look at the facts anymore."

That is probably the best distillation of Tea Party philosophy I have ever heard.

What's more, neither they, nor the Republican leadership, have put forward any credible proposals for either limiting government spending ("Don't touch my Medicare!") or increasing revenues ("No new taxes!") to pay for the entitlements they want.

In fact, more than one American columnist has written that their well-publicized concerns over government spending are really nothing more than a fig leaf for a much deeper anger about the changing social order.

They are, after all, mostly older, white, evangelicals from the heartland and the American South. And they just watched a bill they hated pushed through by a woman (House Speaker Nancy Pelosi), vocally supported by prominent Jews (Sen. Chuck Schumer, Rep. Anthony Weiner), with the help of a powerful gay legislator (Barney Frank), and finally signed by a black president whose middle name is Hussein.

Those facts speak for themselves. The times are still a-changin'. And no amount of threats or slurs will alter that.

Frum, having already been punished for his apostasy, was able to say publicly what McCain and other beleaguered Republicans must want to proclaim themselves: "I'm going to remain a conservative whether they want me or not."