A president launches a war. At first it’s limited, straightforward and popular; congressional authorisation is obtained without difficulty. Few people doubt that American intervention is justified and well-intentioned. Over time, however, the involvement intensifies; casualties mount and doubts grow.

The president leaves office, the end of his term clouded by his war policy. The opposing party takes power, with the new president pledged to decisive action to win the war and bring the troops home. He escalates the US involvement, and when that fails he escalates again.

Meanwhile, the opposing party — the party of the president who began the war in the first place — has returned to its anti-war roots, and largely succeeds in painting the war as immoral, unnecessary and (most importantly) the responsibility of its opponents. As the military situation deteriorates, public opinion turns against the war and against the party now managing it.

Eventually the president leaves office in disgrace, his reputation forever blighted by a war that he made his own.

Readers of a certain age will recognise this as the story of Vietnam, which helped destroy the careers of both Lyndon Johnson and Richard Nixon. But it also bears an uncomfortable similarity to the Afghan war, started by a Republican administration and now being pursued, with increased vigor and ever-diminishing logic, by its Democrat successor.

What’s been missing from the analogy so far is a serious anti-war movement among the Republicans. When Nixon took office, the Democrats quickly turned against the war, but today’s Republicans, outside of the radical fringe headed by Ron Paul, have remained loyal to the Bush administration’s belligerent policies.

Until last week, at least, when Republican National Committee chairman Michael Steele made a bid for the anti-war vote, describing Afghanistan as “a war of Obama’s choosing” and saying “that’s the one thing you don’t do, is engage in a land war in Afghanistan”.

Now there’s nothing inherently impossible about rebranding the the Republicans as anti-war. The party’s traditions are quite strongly isolationist; it was much more reluctant than the Democrats about both world wars and even Korea. As recently as the 2000 election it was arguing against the Clinton administration’s interventions in Somalia, Bosnia and Haiti.

But times have changed, and the strength of pro-war sentiment in the GOP was demonstrated by the angry reaction to Steele. Its leaders and resident ideologues quickly dissociated themselves from his position – some, like Bill Kristol, demanding his removal. His defenders have come almost exclusively from the party’s opponents, such as influential blogger Andrew Sullivan. (The marvellously unhinged Ann Coulter was a rare exception.)

It didn’t help, of course, that Steele already has a reputation for controversy and for inappropriate remarks. Although the Republican Party under his stewardship has enjoyed considerable electoral success, it would seem to prefer that he keeps his opinions on policy issues to himself.

The moral is that for the foreseeable future, Barack Obama (and by extension his Australian ally) won’t have to worry much about attacks from the right on this issue. That doesn’t reduce the importance of finding a way out of the Afghanistan quagmire, but it may perhaps give them a bit of extra elbow room.