During the first Gulf war, all the SCUDs were destroyed by Patriots, according to initial reports. It was only after the war, that we found that essentially none of the SCUDs were hit. We only found out because the Israelis spilled the beans.
So in this Gulf War, let's withhold judgment until the smoke clears. Two things are different, the Patriots have been improved to the PAC-3, and the Iraqi missiles aren't SCUDs, but rather the slower and shorter-range Al-Samoud, which are a much easier target. I tend to believe the new Patriots are doing the job, but I'll wait for the independent Israeli opinion on this, although no missiles have been launched against Israel this time - and the distance far exceeds the 170 km range of the Al-Samoud anyway. That 170 km is 20 km beyond the 150 km limit imposed by the UN. The US cruise missiles like the Tomahawk have a range exceeding 1609 km, by the way.
Some undiscerning folks will call any Iraqi missile or large warhead a WHD. The old US definition pertained to nuclear weapons only. Somehow it was extended to include chemical and biological warheads, too, perhaps because these weapons were restricted by the UN for Iraqi use. The coalition forces (US + UK) can use any cruise missile or daisy-cutter warhead that they please. Asymmetrical rules for an asymmetrical war.
Some folks think the Patriots work too well this time. A British plane war lost to one early in the war, and now the US says the F/A-18C was lost to one too. Who knows what to believe. If the Iraqis were shooting SCUDs, the Patriots would be getting a better test, but let's hope the Iraqis don't try (if they can).
-wg