Chris Christie isn’t a wimp, a hippie or a countercultural icon. He’s not known for taking time out from budget negotiations to smoke dope, or for his sympathy for drug dealers. Yet he’s a soft-liner on the war on drugs.

That the combative New Jersey governor and Republican rock star — just tapped to keynote the GOP convention in Tampa, Fla. — vocally dissents from drug-war orthodoxy is another sign that the tectonic plates of the drug debate are shifting. Perhaps our appetite for spending billions and incarcerating millions, in the service of pieties immune to rational analysis, isn’t limitless after all.

In a speech at the Brookings Institution, Christie called the war on drugs “well intentioned,” but “a failure.” He just signed a law to mandate treatment rather than jail time for nonviolent drug offenders. The Democratic rising star in New Jersey, Newark Mayor Cory Booker, recently condemned the drug war in strikingly similar terms as “big overgrown government at its worst.” In Jersey, the drug war is getting it from both barrels and both parties.

Exhaustion is finally setting in with the enormous human and fiscal costs of attempting to eradicate the ineradicable. People have always used intoxicants, and always will, in ways ancient and new. After all the countless resources expended trying to keep illegal drugs from entering the United States, The New York Times reported the other day, abuse of indigenous prescription drugs is the nation’s biggest drug problem. In 2008, it accounted for the lion’s share of overdose deaths.

A new drug tends to go through a natural epidemic cycle. New users pick it up and spread the word about the good times. Then, it loses its allure as its ravages become plain in the wrecked lives of the hooked.

The metrics say we are “winning” the fight against cocaine. Today, there are only 1.5 million users a month, a drop from nearly 6 million in the heyday of the 1980s. But cocaine’s price hasn’t changed much; its prestige has. “When cocaine stopped being the drug of investment bankers and started becoming the drug of $5 whores, it became less fashionable,” says UCLA professor Mark Kleiman, co-author of “Drugs and Drug Policy.”

The war on drugs overseas, a US foreign-policy priority for decades, has only shifted around trafficking routes. Mark Schneider of the International Crisis Group notes how — in the “mercury effect” — pressure against the cartels in Colombia squeezed the action into Mexico, where it is now being displaced again, to Central America and the Caribbean. No wonder that at the Summit of the Americas in April, Latin American leaders expressed disenchantment with the entire enterprise.

No one crafting American laws from scratch purely on a basis of public health would make marijuana illegal while alcohol — much more damaging to society — is legal. Slowly, the prohibition on marijuana is giving way. Medical marijuana is legal in 17 states and DC. Colorado, Oregon and Washington state will consider ballot measures to legalize the drug in November.

The current regime makes criminals of millions of casual users, but legalization — even in one state — could collapse the price nationally and lead to more widespread use.

Every alternative has its pitfalls. The mandatory treatment now being implemented in New Jersey, although better than a jail sentence, is often less effective than advertised. But we are exiting the era when a focus on the harmful effects of illegal drugs excludes all consideration of the harmful effects of their hard-fisted prohibition. The debate is becoming less susceptible to cheap rhetorical bullying.

If Chris Christie, arguably the toughest Republican in the country, is open to new approaches, there’s hope for everyone else.