When a teenager brings a weapon to an inner-city school and a gang ­shooting erupts, we feel compelled to enact a law requiring “zero tolerance” for weapons at school. Soon a sixth-grader is expelled for using his Scout knife in a ­science project.

So too is it with British Petroleum (BP). As a lawyer might say, “Hard cases make bad law.”

The BP oil spill is indeed a tragedy for the environment we all share. Fishing and tourism on the Gulf Coast are victims of negligence, at least. Clearly, BP must pay for its transgressions. The beaches must be cleaned, hotel owners must be compensated, and government — if it has any role at all — must make sure this never happens again.

Yet as we watch the news coverage that fuels our outrage, we never see the video trucks and news helicopters being “gassed up” with the petroleum products made possible by drilling rigs still functioning. Even when the beaches are cleaned and the motel rooms again ­command $300 per night, ­hoteliers must still rely on oil drills to provide octane for the cars that bring the guests to the surf for a ­summer of ­profit.

Fishermen will also require BP’s best fuel oil to run their boats to the fishing grounds that will one day rebound.

Environmentalists may clean oil-soaked birds with Dawn dish detergent, but its plastic bottle will still be made from petroleum.

The American Dream relies upon cheap and abundant artificial energy. Henry Ford and John D. Rockefeller, scorned by the self-described “defenders of the poor and downcast,” made it possible for even young factory workers to buy cars and take their families for an occasional beach ­weekend.

Except for the most radical of environmental fanatics, a pristine beach has little value if there are no people to envision and enjoy it. And, if the cost of transportation becomes so prohibitive that only limousine liberals can witness the wonders of nature, then Democrats only reveal their hypocrisy as they purport to champion the “working class.” Our goal must be not only to produce energy responsibly, but also to produce more, not less.

“The ‘main thing’ is to make sure the ‘main thing’ remains the ‘main thing,’” one smarter than me said in a speech. In this case, the “main thing” is to keep energy relatively cheap and abundant so as to keep even the least fortunate and hardest-working among us relatively prosperous.

Capping, trading and taxing emissions may make a treasury secretary from Goldman Sachs rich enough to buy the fuel for private planes, but it will still rob from middle-class workers the income they need for a drive to see the dolphins at Sea World or to play beach Putt-Putt.

Banning oil exploration in the Arctic National Wildlife Refuge may be calming to the bears of the Arctic Circle, but it does little good for farmers who grow food cheaply with petroleum-based fertilizers so that a minimum-wage “burger flipper” can buy white bread, a box of grits or a head of lettuce for a buck or two.

Buying organic melons might be a fine thing to add a few more years of life to battle Alzheimer’s, but squeezing the oil industry over an unfortunate incident may choke the life out of those who work the hardest and are paid the least.

With little else to do, a new baby to feed and an ex-wife to support, John Edwards could reopen an office for the express purpose of suing BP for negligence. And as long as BP is made to pay for the damage it caused, I hope Edwards and his group do well for not only themselves, but also for the many who will suffer from the tragedy of the Gulf.

Indeed, the most valuable role of government in this matter may be found in its judicial rather than its ­legislative or executive branches.

As for Congress, it must look to our energy future with the goal of increasing safe energy production, keeping it affordable for all of us. More nuclear power, greater use of natural gas and drilling with well inspected rigs off the shallow waters of the East and West Coasts are requirements for the next few decades at least. We cannot become slaves to the junk science of “climate change,” tricked into using less by raising the cost of energy and lowering our standard of living.

We all want our fishermen to do well. We don’t even mind when a beach huckster feeds his children by selling us a cheap T-shirt with an indecent message that shreds into a rag after the first wash. Yet we must remember that a fouled beach will recover given our time and BP’s money.

But a fouled beach is no ­reason to foul the entire energy environment. The first step in controlling the delicate environmental dance between petroleum and prosperity is to recognize its interdependence and assure ourselves that no bad law will come from this hard case.

Robert M. Levy is chairman of the Moore County Republican Party. Contact him at Law52@prodigy.net.