This line about Iraq by Barack Obama at last night's debate stood out:

When John McCain suggests that we might be there 100 years, that, I think, indicates a profound lack of understanding that we've got a whole host of global threats out there, including Iraq, but we've got a big problem right now in Afghanistan.

Throw out policy considerations for a moment. If the nominees are Obama and McCain, is Barack Obama really going to stand on stage next to John McCain at a general election debate and say he has a "profound lack of understanding" of Iraq and the global terrorist threat America faces?

Isn't that setting himself up to look silly and inexperienced when McCain responds with something along the lines of "When I was five years into my tenure on the Senate Armed Services Committee and already deeply involved in global threats facing America, you were editing the Harvard Law Review."

And won't this be another moment like his "I was tied up at the time" line from the Republican debate earlier this year that brought the crowd to its feet in honor of his service?

Barack Obama certainly represents change, and that will be a powerful weapon against a Republican opponent in a general election, especially on Iraq. But as a pure matter of aesthetics, for him to compete one-on-one with John McCain on national security in the general election, he's going to have to be very audacious indeed.