The U.S. Surgeon General describes tobacco use as a pediatric epidemic. Eighty-eight percent of adults who smoke every day picked up the addictive, deadly habit before they turned 18, according to the 2012 report "Preventing Tobacco Use Among Youth and Young Adults."

That report lays out in devastating detail how adolescents and young adults are uniquely susceptible to social and environmental influences to use tobacco, and the ways tobacco companies exploit that vulnerability, including by spending billions of dollars a year on marketing. Of every three young smokers, only one will ever quit, and one of the others will die of a tobacco-related cause.

The sliver of hope in all these dire findings is that if a kid can make it through his or her teenage years without using tobacco, it’s highly unlikely that he or she will ever start to smoke. The keys, then, are education, prevention and enforcement — including against retailers who profit from this lethal market.

So we applaud Hawaii County for enacting a law that raises the legal age for buying tobacco products from 18 to 21, leading the way not only in the islands but in the country as a whole — only two small Massachusetts towns and New York City have previously enacted similar legislation.

Like other efforts that have successfully made cigarettes less accessible, including the imposition of high tobacco taxes, this law limits young adults’ ability to buy cigarettes at exactly the time in their lives when they would be most inclined to do so. By the time they turn 21, most will have matured to the point that ubiquitous marketing for the product is less of a lure. They’re more immune to peer pressure, more aware of smoking’s dire effects on their health and appearance, and more concerned about the price of a pack.

Extensive research shows this to be true, and the tobacco industry knows it, too — which is why its defenders decry raising the buying age as an affront to the liberty of recognized adults, who at age 18 can register to vote and enlist in the military.

This argument rings hollow. There are plenty of things 18-year-olds generally aren’t allowed to do, such as purchase alcohol or rent a car, for their own well-being and the protection of others. Perhaps it shouldn’t be so easy for impressionable teenagers to join the Army and risk their lives in U.S. misadventures, but that’s a topic for another editorial.

The point is that reducing tobacco use among young people is an important public-health issue and a community imperative.

Tobacco use remains the leading cause of preventable and premature death in Hawaii and the rest of the United States — accounting for 1 in every 5 deaths. Every year, it costs the nation $96 billion a year in direct medical costs and $97 billion in lost productivity.

In Hawaii, as in the country overall, our poorest, least educated citizens are the most likely to smoke, and the rate also is higher among racial minorities. A blanket ban on sales based on age will help erase this inequity, as long as the law is enforced against retailers in wealthy and low-income neighborhoods alike.

The Hawaii County law, which took effect July 1, rightly includes electronic smoking devices, which use nicotine derived from tobacco in e-cigarettes and also are increasingly used to inhale a powerful form of marijuana’s psychoactive ingredient without detection. Retailers must post signs about the new rule at every point of sale and can be fined up to $2,000 if they sell to underage customers.

The Big Island is ahead of the curve with this ordinance, and the state Legislature should pay attention. It should have advanced a similar statewide measure last session.

The evidence is irrefutable that the benefits of preventing young people from lighting their first cigarette last a lifetime. Hawaii County recognized that evidence and acted upon it, for the good of its whole community.