Even if the threat is valid (and the officials in New York believe that this is highly unlikely), it is unbecoming of a great people, like Americans think they are, just to jump in a hole everytime a threat is made. Their behavior in these situations has been programmed into the American People's mind for political reasons, rather than to protect the People from harm. It is a product of the Republican's constant pounding into the public discourse the fantasy that Obama is a weak president, and it is only with the rise of a Republican President and Congress that America can be safe. This desire to "overthrow" this president has nothing to do with safety, but has everything to do with Republicans getting close to absolute power, so that they and their friends in the oil companies can make lots and lots of money.
There is no question that the West really is threatened. But if we allow our society to cease functioning, and if we allow our country to become a place where bigotry wins the day, then the terrorists have definitely succeeded in their goals.