As this has completely slipped my mind... aren't we (that is the international communi-dy) still stopping and searching vessels that may be trying to take things into Iraq?
One presumes that if this is the case, then the three vessels refusing to comply with marine law are prime cases for boarding.
Assuming that the ships do have Iraqi WMD aboard - obviously, we don't want the sea contaminated with lots of nasties, but - if SH has ordered the ships to be scuttled if boarded, he'd lose his WMD stocks. The leakage of contaminants would rather prove that he was lying, wouldn't it? I can't see that there would be any benefit to Saddam whatsoever.
It'd effectively prove the US's case, and protests that 'this was all we had' would be knocked back with 'You said you didn't have any, so why should we believe you'.