An interesting perspective of Ahmadinejad's appearances in NY (including Columbia) in Slate:

I've had the opportunity to attend events with President Ahmadinejad on his three trips to the U.S. (including serving as the interpreter for his U.N. speeches for the last two), and have spent time with his aides and Iranian diplomats during the New York visits. This visit felt perhaps the most politically charged yet, and was certainly the most controversial, even for the Iranians. But amid all the theatrics, Ahmadinejad's political savvy and strategic intentions in New York should not be underestimated.