Lawrence M. Wein of Stanford University has a very good piece in the New York Times about nuclear threat and port security. He talks about the weakness of a counter terrorism security measure that relies exclusively of protecting our ports to prevent the introduction of nuclear weapons into the country. He also talks about the need to be strategic in the security measures we adopt and to weight the cost and benefits of each step.

The best way to view the problem strategically is through game theory. In this case, the government plays first and uses its budget to place detection resources — technology, security experts and the like — at the various “nodes” along the transportation network, like seaports, airports and border stations. The terrorists, in turn, can be expected to choose the path that gives them the best chance to carry out an attack.
As the accompanying chart illustrates, there are a dizzying number of paths that terrorists could use to transport a foreign-built weapon to an American target city — 132 variations, in fact, taking into consideration all four likely modes of transport: commercial airplane, cargo airplane, container ship and cruise ship.
So, how do we decide which route the terrorists are most likely to choose and which path we the are most vulnerable to? Game theory implies that we should maintain an equal chance of detecting fissile material along each of the 132 paths because if we harden one path too much, the terrorists will simply choose an easier one. On top of it all, the agency needs to consider cost-effectiveness: if certain sets of nodes along the transportation network are much more cost-effective to reinforce than others, then the best defense may not come from allocating resources equitably across the system.

However, I would argue that he puts to much faith in detection of fissile material, and he is too fast to dismiss protection of fissile material stockpiles as a first best solution.

First, the terrorists’ obtaining nuclear material and transferring it to a foreign airport or seaport are the two steps that are on all 132 paths, and hence represent excellent choke points. The Pentagon and Energy Department agencies that try to detect fissile material at foreign ports are actually quite well financed and efficient, but given the size of the globe, the number of nations producing nuclear material and the political barriers inherent in working in another nation’s territory, we can hardly assume these efforts are a solid defense of our homeland.

I would actually argue that these programs are extremely important and should be part of a solid defense of our homeland. I am not sure I would argue that they are quite well-financed and efficient, though. More important, he does talk about the lack of investment in making sure that fissile material stays out the hands of terrorists. As Laura Holgate of the Nuclear Threat Initiative simply reminds us, “No fissile material, no bomb.” It’s actually ridiculous how little resources are used to achieve this task (it’s not everyday will you hear me ask for more government intervention!).

I wrote a piece for MIT here last year. Also, I have a paper coming out on this issue soon.

That being said, I would highly recommend reading this article here.