[APBaer]

"How is it in Mexico's national interest to back Saddam rather than the United States?"

Perhaps Mexico, which is a major petroleum producer, does not want the presently shut in capacity in Iraq to come to market and hammer oil prices?

[kesg]

Perhaps Mexico, which is a major petroleum producer, does not want the presently shut in capacity in Iraq to come to market and hammer oil prices?

Maybe, and this is a very good answer IMO, but Mexico surely knows that the US will take out Saddam regardless of how it votes. So why not vote in favor of the US, a vote that may help Mexico down the line on other issues in which it is interested?

[Paulus Invictus]

You struck oil! (and are absolutely right. That's the same reason the Russians are balking on support.)