Jude, how many suitcase sized nukes can you fit into one of these? And how many would it take to destroy Manhattan Island?
We cannot afford to err on the side of incaution. We must be agressive in the war on terror. It is our duty. It is our destiny.
Suitcase nukes are the stuff of yellow journalism and trashy spy novels. They would have to b manufactured by a sophisticated state, of which the US and the Soviet Union alone had the technology to build. The Soviet Union's security struggles in the mid-to-early 1990's would be the only opportunity to steal them. These things, however, would require extensive maintenance - which Al Queda and Iraq could not provide.
Suitcase nukes, therefore, are not a credible threat. (Source)