There are a lot of pros and cons, and I don't claim to have read up on them a ton. From what I have read, I'm skeptical that it's a good idea.
But I do think there is some
merit to the argument in favor of it on cultural grounds, on continuing with life, on, for lack of better words, not letting the storm win
. I recognize, though, that while those arguments are relevant to some people, they're understandably offensive to others who are suffering and concerned that any ounce of services are being diverted from recovery to the marathon.
There will always be people who will say it's "too soon" no matter how long it's been. I mostly try not to think they're right or wrong, even when I disagree. We can have our own answers.
Anyway, I think the big limit to the cultural argument here is that the NYC marathon just isn't a thing for, you know, most people in NYC. It's a huge deal if you're into it. But for the vast majority of people in the city, the marathon is not something they usually pay attention to. It has a tiny constituency when compared to, say, July 4th fireworks, the West Indian Day Parade, or Puerto Rican Day Parade.
After Katrina, some argued that Mardi Gras shouldn't have gone forward in 2006. But it went forward, and I think there the cultural argument was very strong and very right. And, in a very different example, Saturday Night Live coming back two and a half weeks after 9/11 (relatively quickly) was widely seen as the right thing, in part for bringing back some normalcy -- despite the risk that making humor again could be offensive.
Those are examples of the cultural argument being important. For the marathon, the argument exists, but is much, much smaller.