Obama has made the Democratic ticket the ticket focused on foreign policy and national security to a much greater degree than past tickets, and he has campaigned throughout the cycle on the assumption that foreign policy is actually one of his strengths despite his lack of experience. Whether he meant to or not, Biden has done something unusual for a Democrat in emphasizing the dangers and potential threats in the world, which reflects a similar sort of confidence that the Democratic ticket is simply better when it comes to foreign policy.
Yes. This is actually something that appealed to me about Obama from the beginning. He's not afraid of a foreign policy debate, and he's not interested in making foreign policy strength into a test of, "Who's going to bomb more countries?" But he doesn't flinch from it at all. He didn't buy into what Hillary Clinton did, which was that you have to show toughness in the same way that Republicans show toughness in order to be credible on foreign policy. Obama has never been about that.
This is pretty different from how things have gone in the past. The CW is that Democrats win on domestic policy and the GOP wins on foreign policy. Bush's disasters have made the foreign policy mantle up for grabs, and McCain is doing as well as he's doing because he's personally identified with the issue, criticized the conduct of the war, etc. But even so he doesn't really have much of an advantage on the issue.
Larison and others think that Obama's going to wind up being similar to the neocons he wants to supplant. I think he's smarter than that, but if he does a good job he might make Democrats the national security party for a generation, and the GOP will be that much further away from relevance. And a president pretty much makes his own foreign policy, as opposed to domestic policy. The future of American foreign policy begins and ends with Barack Obama, if he's elected.