Nationwide surveillance -- under which on-the-ground inspectors would get access to any suspected but undeclared sites--offers by far the best prospect for detecting clandestine facilities. A known and high probability of early detection followed by the credible prospect of a very forceful international response offers the key to effective deterrence. However, most of the measures that make up the national surveillance package are voluntary under international law, and have to be bargained for -- which is why it makes sense for ElBaradei and the West to bargain for them.
