The weakest part of our political system is the presidential nomination process. And it's not coincidental that it's the part of the federal system that finds least guidance in the Constitution.
There is no provision in the Constitution that says that Iowa and New Hampshire vote first. The idea of giving any two states a preferred position in the process of choosing a president would surely have struck the Framers as unfair.
But we are stuck with Iowa and New Hampshire voting first because no politician who contemplates ever running for president -- i.e., most politicians -- wants to arouse the ire of the political and journalistic establishments of Des Moines and Manchester.
Another feature of the nominating system is that it tends to exclude those with experience in foreign and military policy, the two areas in which presidents tend to have the greatest leeway.
Dwight Eisenhower did have such experience. And Richard Nixon, Lyndon Johnson, Gerald Ford and George H.W. Bush had been vice presidents with varying degrees of involvement in foreign policy and military command.
But the other seven presidents of the last 60 years had to learn by doing. And Ford's ascent came not through the nomination process but through the 25th Amendment.
A third problem is that the lengthiness of the nomination process -- the permanent campaign, as Sidney Blumenthal dubbed it long ago -- means that a president, and the nation, may be stuck with an agenda set as much as 10 years before he leaves office.
And that's in the best case, when a candidate presents a series of policy initiatives to caucus-goers, primary voters and the general electorate, and then tries to follow through in office, as George W. Bush and Barack Obama can claim to have done.
In the worst case, a candidate briefly captures the imagination of impressionable activists and voters with personal glamour and vaporous rhetoric, and then edges ahead of his rivals to clinch a nomination in a good year for his party.
That's what some people think happened in 1976 with Jimmy Carter, though I think that's unduly harsh. Certainly it's a fair characterization of what might well have happened in 2008 if John Edwards had gotten a few more votes and come out ahead of Barack Obama as well as Hillary Clinton in the Iowa caucuses.
None of the politicians currently or possibly running for the 2012 Republican nomination seems to be a shameless charlatan like Edwards. But none except for former Utah Gov. Jon Huntsman has hands-on foreign policy experience either, and he obtained his as Barack Obama's ambassador to China.
The potential candidate who sparks the strongest emotions is Sarah Palin. But her non-spectacular showings in polls suggest that many Republicans, while agreeing that she has been unfairly treated by the press, believe she cannot win. The fates of Sharron Angle and Christine O'Donnell may have been instructive here.
The candidate whom some pundits call the front-runner, Mitt Romney, is hobbled by the fact that the agenda he put together in 2005-06 for his 2008 candidacy contains elements that are undercut by his previous record (on abortion, for example) or are out of line with Republican voters' current thinking (Romneycare).
Romney and Mike Huckabee, good-humoredly fluent and seemingly happy as a Fox News host, both lost the 2008 nomination to a candidate whose strategy was to wait for all the other candidates' strategies to fail. Not a good augury for 2012.
Others carry baggage from the past. Newt Gingrich is sidling up to a candidacy with, as always, a raft of new ideas, many of them good, and some brilliantly penetrating insights, but not much discipline. Rick Santorum, having lost his Senate seat by a 59 percent to 41 percent margin in 2006, is campaigning on the conviction that cultural conservatism will be as important to Republican voters in this cycle as it was from 1988 to 2000.
Tim Pawlenty, Haley Barbour and Mitch Daniels approach running with records as two-term governors and with the chance to propose fresh agendas. But for the moment they're overshadowed as congressional Republicans try to seize the initiative on major policy.
It is easy to see at least one reason why each of these potential candidates must lose. But our unsatisfactory nomination process, for all its faults, is a zero-sum game in which one player must win.