I'd like to second Josh's thoughts about the considerations that should go into Obama's veep selection, but let me amplify one of them: the veep choice should have a good working relationship with the nominee. Josh is right that picking a runningmate is basically the equivalent of making the first pick in the NFL Draft, but there's one big difference: The top pick in the NFL draft initially has more clout than his coach; the number two person on the ticket is always going to be in a subservient position to the person at the top.
I bring all this up because, while I'm very intrigued by the idea of Jim Webb as Obama's runningmate for all of the obvious reasons, one thing I haven't seen much discussion of is whether Webb is too independent to be a good veep. The one prominent political position Webb has held in which he's had to work under someone--as Reagan's Secretary of the Navy--didn't work out too well, with Webb resigning after clashing with his boss, Defense Secretary Frank Carlucci.
Here's the lede of the New York Times 1988 editorial on Webb's resignation:
It's a fine thing to resign on principle. But James Webb seems to have resigned as Secretary of the Navy on something closer to pique. He failed to get on with his boss, Secretary of Defense Frank Carlucci, and left with a gratuitous personal blast. Mr. Webb's departure raises no great debate about the future of the Navy, merely an eyebrow as to whether he was really suited to his office.
Now, granted, this was 20 years ago. From all accounts, Webb's worked well in the Senate (and the coalition he was able to assemble around his veterans legislation was certainly impressive). But Senators ultimately answer to themselves. Webb wouldn't have that luxury as veep. If he came out on the losing side of a policy debate in an Obama administration, would he be willing to support that policy? I don't know. Perhaps. But have Evan Bayh or Ted Strickland or even Ed Rendell ever resigned from anything--whether on principle or pique?