Back during the primaries, when Obama and Clinton were running neck and neck, I had more than a few conversations with friends about who would be the better pick.

My take was always the same: Obama, with his unique mix of public rhetoric and personal biography, would be better for the country; Clinton, with all the foreign goodwill and experience she and her husband could marshall internationally, would be better for the world. I just wasn’t sure which was more important. 

Yet I’d also add that while there was little Clinton could do to grow her base domestically, there was plenty Obama could do to shore up his foreign policy credentials.

Tapping advisers like Samantha Powers was a good start, but as Powers own gaffe demonstrated, Obama needed advisers and officials whose familiarity with foreign policy extended well beyond the academic or theoretical. In short, he needed to explicitly ally himself with someone like Biden—the Senator with the greatest familiarity with Iraq, and a pretty solid grasp of central Asia more generally. If Obama were to publicly tap Biden, I’d say, I would probably fall into his camp.

Of course, that never happened. The Democratic primary was all about America—or rather, about how American liberals wanted to see themselves—and Obama was able to win on that count alone. Save for his Iraq vote, foreign policy never really factored in in a decisive way.

However, as David Axelrod has finally begun to realize, Obama will not be so lucky with the general election. That’s why he went on his speaking tour in June and why he tapped Biden now. Forget what the pundits say: this pick was not about domestic issues, or the so-called blue-collar vote. Look at the electoral map, and this year’s campaign is going to come down to a couple mid-Atlantic states and a handful of Western ones. If Obama can take the right mix of those states, he wins. Biden helps in that regard, but either Bayh or Kaine would have helped more.

Picking Biden was all about foreign policy—about having someone who could hold his own against McCain’s foreign policy credentials in the short run, and even more, about having someone who could help Obama recalibrate American foreign policy once he takes office. (Incidentally, if there’s one thing the media has not talked about enough in this campaign it’s this: the complex political manuevering that will happen in 2010-11, when the US will have to disengage from Iraq without empowering Syria or Iran. That will be the major foreign policy challenge of the next administration; and in that sense Biden’s selection was made more with an eye toward 2012.)

All of which is to say, Biden was a good choice for Obama. Not great, since the same lack of discipline that defeated Biden’s every presidential run could prove a liability once in office.

But certainly a good choice nonetheless.

In the near term, Biden will help to counter McCain’s principal strength. In the long term, he could prove invaluable—should Obama win, the next election will be a referendum on his governance abroad and at home, and Biden’s advice will figure prominently in former.