When you hear Republicans disparage Sen. John Edwards's lack of experience, remember the words of Sen. Orrin Hatch, spoken to George W. Bush at a debate on Dec. 6, 1999.

"You've been a great governor," Hatch declared of his rival for the Republican presidential nomination. "My only problem with you, governor, is that you've only had four and going into your fifth year of governorship. . . . Frankly, I really believe that you need more experience before you become president of the United States. That's why I'm thinking of you as a vice presidential candidate."

Which is exactly what Edwards was chosen for yesterday.

Republicans were in a foul mood because Kerry's choice of Edwards as his running mate muddied up all the story lines they were itching to trot out. To understand why Edwards was the best choice for Kerry, consider what the Republicans (and, yes, the media) would have said if the nod had gone instead to Rep. Richard Gephardt, the clear runner-up in the vice presidential stakes.

Kerry would have been described as "insecure" at the prospect of standing next to the "charismatic" and "populist" Edwards. Fearing being "upstaged" by the equally ambitious Edwards, Kerry would have been accused of making the "obvious," "uninspired" and "comfortable" choice. Gephardt's experience would have been trotted out to turn him into the "tired" face of the "old" Democratic Party. It would also have been said that Kerry, the "elitist Massachusetts liberal," had "written off" the South and rural America.

This would have been unfair to the decent Dick Gephardt, Kerry's sentimental favorite. But Kerry's political advisers knew the price of picking the old warhorse, which is why they formed an Edwards lobby inside the campaign. Kerry, who had known Edwards mostly as a rival, concluded that Edwards would be a loyal partner -- Edwards's political future now depends entirely on being a great running mate -- and the one choice who could expand the campaign's reach.

Putting a Southerner on the ticket was essential. Since 1960 five of the eight Democratic tickets that included a Southerner have been elected. The tickets without a Southerner went 0 for 3. Edwards allows Democrats to contest North Carolina, Florida, Louisiana, Virginia and Arkansas. Democratic optimists -- yes, it's a stretch -- think Edwards's native South Carolina might also be in reach.

Forcing the president to compete on terrain he had mostly considered safe alters the election's dynamics. And in the primaries, Edwards's appeal seemed strongest in constituencies that the Democrats must win over. He ran especially well among rural voters and appealed simultaneously to blue-collar whites and upper-middle-class professionals.

The key to Edwards's twin appeal -- to upscale voters and to those trying to climb the ladder or helping their kids do it -- was explained many years ago by the great American sociologist Seymour Martin Lipset. Lipset argued that the two core American values were "equality" and "achievement." Americans want a level playing field and don't like people who put on airs. But they also admire strivers. Edwards can give his "two Americas" and "dad in the mill" speech as someone who used the education system to rise up and get rich. That's the American story.

Ah, but he got rich as one of those "trial lawyers," Republicans were quick to say. This fight over trial lawyers will be one of the campaign's great sideshows. The Republicans failed with the anti-lawyer gambit against Edwards when he was first elected to the Senate in 1998. Here's a bet that when trial lawyers are paired up against corporations that abuse their power, Edwards's profession will have a fighting chance.

Republicans grumbled that Edwards was Kerry's "second choice" after Republican John McCain. Can't blame the GOP for trying. But it's hard to think voters will hold it against Kerry that he tried to reach out to Republicans during a period of rancid partisanship.

Oh, yes, and one more point on that experience thing: "When it comes time to make the decision to send our young men and women into harm's way, that decision should be made by a leader who knows that such decisions have profound consequences. There comes a time when our nation's leader can no longer rely on briefing books and talking points." That was McCain in 1999. He was talking about the man who became our current president. You wonder which side will be most eager to cite that quotation.