Are the Patriots working this time?

Iraq has now apparently fired some Scud missiles in the direction of Kuwait. (These are the same Scud missiles the Iraqis denied having. "Oh. You mean these Scud missiles"). It is being claimed that two have been shot down with American Patriot missiles. It is worth recalling that in the 1991 war the Americans initially claimed close to a 100% success rate at shooting down Scuds with Patriots, but in the months following the war the success rate claimed steadily dropped, ending up at less than 10%. As it happened, a major reason why the Scuds were exploding in mid air was simply that the second stage that the Iraqis had added to the Russian Scud missile (which is itself based on the German V-2 design - that's right, we are talking a World War 2 weapon here) was badly designed and built and the missiles had a tendency to break up by themselves.

Undoubtedly the Americans have in the twelve years since spent a lot of money improving the performance of the Patriot, and it will do better this time. However, one should always be sceptical of grandiose claims about its effectiveness. Shooting down missiles in flight is extremely hard.

Update: There is a good piece in Slate (and further links) talking about the failure of the Patriot missiles in 1991 and just how the new version has been supposedly improved from the old version. The attitude this time seems to be that the authors of the article will need to be shown pretty strong evidence before they believe the Patriots work.