Oh for the lost art of short biographies! The thought struck me the other day as I was rereading Roy Jenkins’ lapidary life of President Harry Truman, founder of the Pax Americana that George Bush seems well on the way to destroying. Including references and index, it came to just 232 pages.

For figures infinitely less consequential than Truman, you’re lucky these days not to have to wade through three times as much — and, given the qualities of Jenkins as both writer and historian, for a quarter the reward.

But, you may ask, why Truman? Simply because he is the historical figure Bush most looks to for solace in this dismal final chapter of his own presidency. And certain similarities are undeniable. For both, a foreign war — Korea in the case of Truman, Iraq for Bush — was the dominant issue in their last two years in the White House. Both became intensely unpopular. If you think Bush’s present approval rating of around 30 percent is bad, what about Truman who left office with one of 23 percent? Yet he is now deemed one of the near-great presidents, right up there behind the troika of Lincoln, Washington and Franklin Roosevelt. He may have made a host of petty mistakes, historians agree, but the big things — NATO, the Marshall Plan, containment of the Soviet Union — he got triumphantly right.

Churchill told Truman later that “I misjudged you badly,” and that since Roosevelt’s death, “you more than any other man, have saved Western civilization.” As his own presidency implodes, Bush clings to the hope that events, even after he leaves office, will lead to a similar re-evaluation of the Iraq war; and that he, like Truman, will be hailed as a savior of Western civilization, by posterity if not by his own ungrateful and uncomprehending contemporaries. The differences, of course, are equally striking. For a start, Bush’s unprovoked invasion of Iraq was entirely a war of choice; the US involvement in Korea was in response to the invasion of the South in June 1950 by North Korea, backed by communist China, itself then an ally of Stalin’s Soviet Union. For all his lapses into pettiness, Truman knew how to surround himself with great men such as Dean Acheson and George Marshall. Mention Dick Cheney and Donald Rumsfeld in the same breath and the reaction is a sour laugh.

Even so, the political cycles coincide almost perfectly. Truman’s last midterm elections, in which his Democrats lost seats but narrowly retained control of Congress, were pretty dismal — though not as dismal as last November’s loss of both Senate and House by Bush’s Republicans. In both cases, two leaders of whom the country had tired played out their terms, locked in place by a rigid constitutional system. Had Bush been a European prime minister, dependent on the support of a majority in Parliament, he would surely by now have been replaced by a new leader. The same perhaps might have applied to Truman half a century ago.

But he soldiered on, and in Jenkins’ words, “The best that could be said for this final year and a half” (between the stalemate that settled on the Korean War in mid-1951 and Truman’s leaving office in January 1953) “was that by the standards of his presidency, relatively little happened in it.”

Somehow, I doubt the same will be said by future historians of the 660 days remaining to the present occupant of the White House.

These are strange political times in Washington, and weird things could happen. And I’m not the only one to feel this way. Take the extraordinary comment of the conservative columnist Robert Novak. If anyone can glory in the label “veteran,” Novak can. When it comes to relations between the White House and Congress nobody knows more. In half a century, he wrote in The Washington Post this week, he had not seen a president as isolated from his own party in Congress — “not Jimmy Carter, not even Richard Nixon as he faced impeachment.” Not even Nixon? That is something.

And is it a coincidence that the “I-word” is being murmured on Capitol Hill, not by Democrats, but by a leading Republican? To be sure, Chuck Hagel, the senior senator from Nebraska who broached the topic, is not your typical Republican. He has turned into an impassioned foe of the Iraq War, and may announce a bid for the presidency himself later this year. In short, Hagel has an agenda.

By contrast, and for all their dislike of Bush, leaders of the Democratic majority in Congress profess not to be interested in launching impeachment proceedings. It would, they say, be a time-consuming distraction, and more likely than not it would unite Republicans around their president — the precise opposite of what Democrats want to bring about. Given their slender majorities in House and Senate, the party’s only hope of imposing its will on the White House is to win the support of enough congressional Republicans to override a veto.

It could just be, however, that this president will play into their hands. For consider another unusual ingredient in the political mix. This is an utterly open election. Even Truman briefly contemplated running again in 1952 — and his vice president Alben Barkley did so but failed to win the Democratic nomination. Not since 1928 has there been an election like 2008, when neither an incumbent president nor vice president is in the race.

This means that the outgoing Bush has no need to tailor his Iraq policies to help Dick Cheney to win the election (as Bush would put it, to pander to the polls). In other words, he can give full rein to his sense of destiny and quasi-religious conviction that he was right and remains right on Iraq, however much the country has soured on his war.

Now listen to Hagel. “The president says, ‘I don’t care.’ He’s not accountable any more — which isn’t totally true,” the senator mused aloud in an interview with Esquire. “You can impeach him, and before this is over, you might see calls for his impeachment. I don’t know. It depends how this goes.”

It wasn’t a threat — merely an observation on what conceivably could happen if the war continues to be a disaster, if Congress continues to demand the troop withdrawal in 2008 favored by almost two-thirds of the American public, and the White House continues to ignore it.