A summer holiday from the federal gas tax is a bad public policy idea for many reasons, but especially so in South Dakota, where federal gas tax revenues pay for 75 percent of all our highway construction.

In a bit of campaign posturing that sounds more like political pandering than prudent energy policy, presidential candidates Sen. John McCain and Sen. Hillary Clinton have both called for the federal government to give consumers a vacation from the federal gas tax this summer. Sen. Barack Obama is right to deride the gas tax holiday as a typical Washington, D.C., response - a short-term fix to a problem that needs a long-term solution.

A three-month hiatus from the tax would save the average South Dakotan only about $30 at the gas pump, according to estimates from the American Road & Transportation Builders Association. Obama's camp predicts the holiday would cost the state millions more in lost highway funds.

Everything from new road construction to patching potholes to highway bridge safety, relies on revenue from the federal highway trust fund and the 18.4 cent-a-gallon federal tax on gasoline that funds it. The federal highway fund is already a shrinking resource, as consumers try to conserve gasoline by driving less and lowering consumption when prices soar at the pump. Federal officials warn the federal highway trust fund will lose billions as we tighten our belts in these uncertain economic times. Eliminating the tax temporarily would weaken a funding source that's already on shaky ground.

Here in South Dakota, we get about $2 back in federal monies for every $1 of the federal gas tax we pay, so we should have little incentive to support a gas tax holiday. Doing so could guarantee a 28 percent drop in highway revenues, cost the state $46 million in highway funds and threaten more than 1,600 highway-related jobs. Clinton favors replacing the gas tax at the pump with a windfall profits tax on oil companies, a solution with its own problems.

Saving consumers a few dollars at the gas pump isn't worth the potentially devastating effects to our highways and bridges that delaying needed maintenance might cause. Are our political memories so short that we have already forgotten the collapse of the I-35 bridge in Minnesota last year?

We hope not, because South Dakota already faces a $600 million shortfall in highway and bridge work.