Bill Kristol thinks that Romney’s performance in the last debate on foreign policy could determine whether Romney wins or loses the election:

Foreign policy isn’t Romney’s natural subject. It’s not his comfort zone. And it’s always more difficult for the challenger. Good. Romney will have to rise to the occasion.

This has remained one of Romney’s biggest weaknesses for a few reasons, the most important of which is that he simply hasn’t spent enough time or paid enough attention to these issues to be as well-versed in them as he should be. There are many things that aren’t Romney’s “natural” subjects, but he doesn’t struggle with any other kind of policy as much as he struggles with this one. As a former governor, it is understandable that he prefers talking about domestic policy issues, but favoring this preference has caused him to neglect foreign policy to a remarkable degree for someone who has been running for president since 2006. Until now, most voters likely haven’t noticed the result of this neglect, but they will see it in Monday’s debate.

One of the telling moments during last night’s debate was Romney’s response to the question about his differences with George W. Bush. He tried to distance himself from Bush on energy, trade, deficits, and Republican support for “big business.” Some of these differences aren’t real and some aren’t significant, but those are the things that Romney chose to emphasize as his biggest differences with Bush. The woman asking the question also referred to “international problems” that she blamed on the Bush administration, and expressed her fear of a return to Bush-era policies. It should have been easy for him to say, “My foreign policy will differ significantly from that of President Bush in the following ways.” He didn’t address that part of her question, perhaps because he didn’t see a way he could reassure the questioner without alarming his supporters, or perhaps because it didn’t occur to him that he needed to distance himself from Bush’s foreign policy failures.

It would be reasonable for the questioner and the public to conclude from his response that there aren’t any major differences between Romney and Bush on foreign policy. That is what all of the other evidence to date confirms, and given the opportunity to distinguish himself on foreign policy Romney opted to talk about other things. Romney could correct that oversight in Monday’s debate, but I wouldn’t count on it. If losing the foreign policy debate means that Romney “probably won’t win” the election, as Kristol says, then Romney probably won’t win.