Last summer when gas cost $4 a gallon, Americans' demand for large gas-guzzling vehicles dried up like the morning dew under a hot summer sun. Small cars that got great gas mileage quickly became the new rage.

Consumers' change of appetite added to the woes of Detroit's Big Three, because trucks and SUVs were their best sellers. They couldn't change fast enough to accommodate consumers' new taste for fuel-efficient cars.

But since last summer, oil prices plummeted -- and pump prices are the lowest they've been in years. And just like that, Americans' appetite for big vehicles is returning.

Even though overall auto sales are still struggling due to the credit squeeze and recession, demand is leaning toward big cars again. Locally, Gerald Jones General Manager Brian Winters says SUV and truck sales are up 37 percent since September when pump prices peaked at $4 a gallon. Similar spikes in big vehicle sales are confirmed by national surveys.

It appears U.S. consumer demand for big cars will again shift into high gear as the recession recedes -- providing gas stays reasonably priced. Today's average is $1.65.

Consumers are only slightly less fickle than oil prices. Oil is a commodity with wildly fluctuating prices that not even OPEC can control. Even so, this much is certain: The stronger the economy grows, the higher fuel prices will rise; the slower the economy, the lower the price.

The low fuel prices we see today will last only as long as the recession -- which we all hope will not be long.

Smart consumers know this, and they will continue to buy fuel-efficient vehicles -- and push for hybrids and other technological changes in auto making that will lessen this nation's dependence on oil.

The problem is, to hasten this development, Nanny State activists are urging Congress and the incoming Obama administration to impose a gas tax that would return pump prices to $3.50 to $4 a gallon -- and keep them there.

That would be a big mistake.

It's almost always a mistake for government to use its taxing authority to control people's behavior. That's an abuse of power that violates Americans' fundamental freedom: the right to live our lives and spend our money in ways that other people don't approve of. Sky-high gas prices also curtail poor and low-income Americans' freedom to get around, including going to work.

Using taxes to boost pump prices to unconscionable heights is also a nonstarter. It would reduce discretionary spending in other areas, thereby depressing the economy.

Another Nanny State idea is to have government ban production of large vehicles, leaving only small, fuel-efficient cars for the public to buy. In other words, force the Big Three to make cars without regard to consumer demand.

What next? Will restaurants be forced to offer their most unpopular appetizers?

Government has no business being the arbiter of what consumers buy, unless it directly affects their health or safety -- which auto purchases do not.

Uncle Sam may not agree with consumers' auto choices, but it's their choice to make, not Big Government's. In our free-enterprise society, the consumer is king -- and that doesn't need to change. This is why automakers must be allowed to produce what consumers want.