Quick show of hands: Who among us expected that, in the course of the convention acceptance speeches by John McCain and Barack Obama and throughout the three debates in which they face each other in the fall, the words “South Ossetia” might be mentioned again and again? Or that the nation of Georgia might loom larger over the November election than the state of Georgia?

This is the thing about presidential elections — they can turn on a dime. This one has already. The success of the surge is playing a complex role in the calculations of both camps, with the possibility of a clear victory in sight in Iraq before anyone actually casts a vote in November. For a time, it appeared the surge victory might, in an odd and unexpected way, help Barack Obama by taking Iraq off the table as a source of anxiety and allowing him to focus the election more specifically on the economy. But Obama’s own uncertainty about how to address the surge suggests otherwise.

The role of foreign policy and diplomacy was bound to take center stage in the fall in any case, because Iran seems intent on keeping its nuclear program at the center of worldwide discussion. The complexities there, at least regarding the time frame in which Iran might actually become a nuclear power and the possibility of Israel’s moving to take care of the crisis, was always bound to lead to fuzzy answers about hypotheticals. But the very real fact of an old American enemy, Moscow, either dismembering or swallowing up anew a democratic American ally aborning, Georgia, is a different matter. This may prove to be an ongoing crisis in a key part of the world in the middle of an American election, and there will be no avoiding the question by alluding to hypotheticals.

At the end of last year, I said that the assassination of Benazir Bhutto in Pakistan represented the end of the primary season’s holiday from history. Obviously, I was wrong about that, perhaps because primaries are largely conducted among voters who want their preexisting questions answered and don’t care so much about the responses of candidates to issues of the moment. General elections are about something else — they are about how the candidates might conduct themselves in the Oval Office. In these circumstances, the issues of the moment are vitally important because they speak to how quickly a candidate can respond to a crisis and how unexpected problems fit in with the more general agenda a candidate has been laying out in the months and years previous.

So welcome, South Ossetia, to the presidential election of 2008. Ere long, we won’t even remember we had no clue where you were only a day or two before the Olympics began.