[Elspode]

Drop a MOAB in Times Square on New Year's Eve and you will most definitely be using a WMD.

I think the term is generally being applied (for purposes of Iraq, anyway) to anything that isn't used in traditional land-based combat, anything that will kill more than a few hundred people in a single delivery/detonation.

Bio, chemical and noo-kew-luhr weapons will, with certain limitations, do that, so that's what they're looking for. If Iraq had a MOAB, they'd consider that to be one too, I'm guessing, as its blast radius is enormous.