John McCain had his "I don't understand economics" moment; Barack Obama had his capital-gains tax fiasco.

Now, Hillary Clinton has had her own run-in with the dismal science on ABC's "This Week." Jonah Goldberg reports that on Sunday's show, George Stephanopoulos asked the senator "how she can defend her proposal to suspend the federal gas tax for the summer when everyone knows it won't lower gas prices":

Clinton says she doesn't mind if every economist in the country agrees that her proposal would do absolutely nothing to alleviate high gas prices. Indeed, when Stephanopoulos pressed her to name one--just one!--credible economist who thinks this idea has any merit, she responded: "Well, I'll tell you what, I'm not going to put my lot in with economists." Instead, she explained, she's going to break with the "government power and elite opinion" and side with the little guy.

Indeed, unlike John McCain, who also stupidly supports a gas-tax "holiday," the Clinton plan has the added benefit of punishing those evil oil companies by making them pay the tax. The same irrelevant economists insist that the oil companies would simply pass that cost back to the consumers, and the "tax holiday" would artificially hike demand for gas so that pump prices would jump right back up. But never mind that.

Candidates are just starting to catch some heat for their stances on the gas tax, and, as Goldberg points out, the plans are likely little more than hot air. The general willingness to disregard facts for political expediency, however, is certainly instructive--and worth a mental note.