You’ve heard of the American antiwar left. You may not have heard of the American antiwar right. It exists on the margins and comes in two main varieties.

The first is the realist school of the first President Bush, his national security adviser Brent Scowcroft, his secretary of state Jim Baker and the new defence secretary Bob Gates. The second is the traditional isolationist wing of the old Republican party – the party that opposed entrance into the second world war, and has the Founding Fathers’ fear of entangling foreign alliances foremost in their minds.

Both schools have been in eclipse in the current administration and Congress. But both also seem to be stirring somewhat in the wake of the chaos in Iraq.

Two weeks ago 11 Republican congressmen walked into the White House and gave George W Bush one of the starkest responses yet to his Iraq strategy. They told the president that if there wasn’t measurable, tangible progress in Iraq – politically and militarily – by September, they were going to join the Democrats in cutting off or placing conditions on funds for the war.

They told him, according to anonymous sources, that even then they would not accept his judgment on the matter. The president, they declared, had no credibility with their constituents. They wanted to hear from General David Petraeus, the commander of coalition forces in Iraq. These people, remember, are Republicans.

They have allies. Bob Gates has explicitly argued that the point of the surge is to create the conditions for withdrawal, not entrenchment. Republican senators Chuck Hagel and Gordon Smith from Nebraska and Oregon are already on record with the Democrats on continued funding for the war. A section of Washington’s Republican elite – from Colin Powell’s circle to the senior military brass – now believe the war has been a terrible mistake, and are biding their time until the president and vice-president confront what they view as reality.

But what few expected was the emergence in the first two debates among Republican presidential candidates of an obscure and somewhat cranky congressman from Texas, Ron Paul, voicing old-fashioned small-government, freedom-loving, peace-making Republicanism.

Paul looks like Ian McKellen’s dotty uncle, and ran as the Libertarian party candidate for president in 1988, winning a grand 0.47% of the vote. In the Congress, Paul has never voted for a tax increase, he has criticised Ronald Reagan for deficits, voted against the Patriot Act, against the Iraq war and against any law that he regards as an unconstitutional overreach by the federal government. That means almost every law on the books.

He still hasn’t recovered from FDR. For good measure, he wants to abolish income tax. Yes, he’s a bit of a crank. But he’s been reelected in Texas several times by large margins.

And even cranks have a point sometimes. In last Tuesday’s Republican debate, he electrified the crowd by arguing that Islamist terror is partly fomented by US policies in the Middle East.

“They attack us because we’ve been over there,” he declared unblinkingly. “We’ve been bombing Iraq for 10 years. We’ve been in the Middle East [for years]. I think [Ronald] Reagan was right. We don’t understand the irrationality of Middle Eastern politics.

“Right now, we’re building an embassy in Iraq that is bigger than the Vatican. We’re building 14 permanent bases. What would we say here if China was doing this in our country or in the Gulf of Mexico? We would be objecting.”

The crowd in South Carolina started to applaud Paul’s derision of a distant war until they were cut off by the Fox News questioner, and then by Rudy Giuliani, who accused Paul of saying that the US deserved the September 11 attacks.

Paul rejoindered later that he said no such thing (and the transcript proves him right). He also cited the 9/11 Commission report that cites the issue of “blowback” in exacerbating the rise of Islamism in the Middle East.

This is surely an unremarkable observation. Yes, the US did nothing whatever to deserve 9/11. And Al-Qaeda’s extreme theology provides plenty of justification for suicide bombing and mass murder. But the US bases in Saudi Arabia were clearly part of Osama Bin Laden’s grievances, just as America’s support for the Shah obviously paved the way for the 1979 revolution in Iran.

The world is complicated and actions generate reactions. History is dynamic and unpredictable. Weighing the consequences of various initiatives in the Middle East is just common sense in making foreign policy. It isn’t self-loathing on the part of Americans.

Paul also has serious online support. Like Howard Dean – another crank – Ron Paul’s supporters are overrepresented on the web. They blasted all the online polls about the debate, and Paul thereby “won” or came second in the debate, according to the ABC News poll, the Fox News poll and almost every other online poll out there. His campaign has deployed YouTube to great effect as well, and the hostility of the Republican establishment has only given his little political insurgency more oxygen.

Perhaps most enduringly, his very presence reminded Americans of what the Republicans used to be. They were once the fiscally prudent, freedom-loving isolationists of the United States.

The idea that the party of Eisenhower or Goldwater would have suspended habeas corpus indefinitely, as Bush has done for “enemy combatants”, would be unthinkable. The idea that they would have tried to occupy and rebuild an entire country in the Middle East is unimaginable. They were ferociously anticommunist, but also wary of direct engagement in foreign countries and deeply suspicious of all wars.

This kind of prudence and caution was once the hallmark of the middle of the country and its Midwestern American values. Paul reminded Americans of this past. He told them that the Republicans opposed the second world war, ended the Korean war and ended the Vietnam war. Why not the Iraq war? Why not indeed.

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