I do not live in "the city" (as evidenced by the fact that New Yorkers calling it "the city" continues to annoy me).  But I will establish my cred by saying I lived for many years in DC, including on 9/11.  And I have (on an earlier occasion) been the victim of a terrorist attack.  But on topic: in DC I was REGULARLY inconvenienced by the workings of government and political events, including once when I was stopped by a motorcade while on the way to the emergency room.  I have spent large blocks of time in Paris as well, and barricaded zones full of protesters are a regular occurrence there, and they still manage to get their bread and cheese every day.  New Yorkers have been dealing with the annoyances of the UN for a half-century, with all of the security hassles and dangers that come with it.

They will not need to shut down all of Manhattan for this trial any more than they needed to shut down all of DC when the president regularly spoke at the Hilton across the street from my home.  They will shut down a few streets here and there when they move people around, but the trial will not be a multi-acre affair...it will take place in a single room in a building already considered a terrorist target and already heavily guarded due to the fact that IT IS A COURTHOUSE AND THERE ARE CRIMINALS THERE.  Also: Manhattan is a really crowded place and nobody has ever has an expectation that they can drive from point a to point b in any reasonable amount of time (though they all claim to know secret shortcuts to La Guardia).

Aside from the obvious fact that the level of unemployment does not negate the fact that we are a free and democratic country, there is nothing about this trial that will further depress the economy of New York.