I forget the charge but something along the lines of "making a terroristic threat", and I don't believe the law considers one's actual ability to execute said threat. This isn't a 1st Amendment issue. Working for a news org does not give you free reign to say whatever the hell you like.

Consider this; If an FBI agent wanted to arrest this man, the request would get kicked all the way to the top because no one wants to risk their ass, especially on a case that would instantly be dropped once it hits Patel's desk. Still, I would think someone with authority in NYC would take this seriously.

One more thought, bet money the UN Building is on high alert for stochastic terrorism.

EDIT:

Must not be a federal law, all I'm seeing are state laws. Here's the criteria from NY State:

INTENT means conscious objective or purpose. Thus, a person acts with intent to intimidate or coerce a civilian population, influence the policy of a unit of government by intimidation or coercion, or affect the conduct of a unit of government by murder, assassination, or kidnapping, when his or her conscious objective or purpose is to do so. 4 In order for you to find the defendant guilty of this crime, the People are required to prove, from all of the evidence in the case, beyond a reasonable doubt, each of the following two elements:

That on or about (date), in the county of (county), the defendant (defendant’s name), threatened to commit, or to cause to be committed, the offense of (specify offense), thereby causing a reasonable expectation or fear of the imminent commission of that offense; and
That the defendant did so with the intent to intimidate or coerce a civilian population, influence the policy of a unit of government by intimidation or coercion, or affect the conduct of a unit of government by murder, assassination or kidnapping.

Sounds like he'd slide. :(