The Iranian guys,who were supposed UN security ( hahahahaha) were talking pictures of the Brooklyn Bridge and tunnels and such. But those places are heavily watched and will be long after the convention.
I really doubt the terrorists have dirty bombs/nukes.If they had them,they'd have used them already.
Then, if not dirty bombs....What? There were, if you recall, lots of Arabs seen taking lots of pics, all over the U.S. I remember a long time ago at the Hoover Dam, too. And of course, we remember all the Arabs at small plane air training schools.....etc.
I am sure they were just tourists taking pictures. : >) I believe we gave these thugs back to Iran.