Nuclear Weapon Going off in Manhattan

According to the US President-The Greatest Threat:

President Obama feels that the greatest threat to national security is from that of terrorism, and involves nuclear weapons.  This is an unfortunate consequence of widespread nuclear proliferation.

Obama says he's more worried about the possibility of ‘nuclear weapon going off in Manhattan’ than Russian threat

The President says the Russians ‘don't pose the No. 1 national security threat to the United States,’ despite the Kremlin's land grab of Crimea.

BY JOSEPH STRAW  NEW YORK DAILY NEWS Published: Tuesday, March 25, 2014, 12:59 PM