When you want cogent thinking about terrorism, you go to Steve Coll. Which is what I did this morning:

Jeffrey Goldberg: Do you think al-Qaeda is planning an "October surprise," an attack on an American target, here or overseas, in order to influence the election?

Steve Coll: AQ leaders, maybe because they spend a lot of time trapped and bored in safehouses, seem to be obsessed with calendars. They like anniversaries and they pay attention to elections abroad. So I'm sure they have the American election in mind. My last well-sourced conversation is a few weeks dated, but last I checked the US intel system was very quiet in terms of "chatter" or other indicators of any attack in the U.S. What seems more likely are more attacks against US-affiliated targets in the Pak-Afghan region, coupled with media tape releases, similar to Osama's election-eve video of 2004. They like to be heard at big moments in American politics, and this campaign is certainly such a moment.

JG: What do you think the next President's first Pakistan-related crisis will be? Will it be prompted by intelligence suggesting that Pakistan's nuclear program is no longer secure, or will it be the need to put ground troops into the tribal areas? Or something else entirely

SC: The big in-box item is going to be fixing Pak-Afghan strategy comprehensively. What to do about the tribal areas will be at the heart of that. Petraeus and the Joint Chiefs will present the next president with some sort of plan, but exactly what it will be, and how radical a departure from current policy it will represent, I'm not sure. More troops, more politics, more jobs for angry young tribal men - something along those lines.

JG: Would a "surge" in Afghanistan work? How many troops would it take to secure the country?

SC: I really don't know. US ground troops, as in Iraq, can at best buy time, create some breathing space to get a larger and more capable Afghan force fighting effectively. That effort so far has been hobbled by under-investment. It is not as constrained by sectarian problems as the Iraq project has been, but it isn't easy. The troop number question is embedded in the training-of-capable-Afghans question.

JG: Is Yemen drifting into the camp of America's adversaries?

SC: Yemen is such a strange country - I'm not sure that it will ever find its way into anybody's camp. Chew and discuss.

JG: I stopped staying at the Marriott in Islamabad several years ago, thinking it was a bomb-magnet. Had the thought occurred to you as well?

SC: I have a blog post going up on Pakistan today, in theory at least, which contains a little elegy for the Marriott nee Holiday Inn, my onetime home away from home. I cut down on staying there recently for the same reason, but nostalgia drew me back sometimes. I asked for rooms facing the back, figuring the truck bomb would arrive out front - as it happened, that wouldn't have done much good.