U.S. Sen. Mitch McConnell is currently pushing for raising the minimum legal age to buy tobacco products from 18 to 21 nationwide. That’s a great idea, but it doesn’t go far enough.

It may seem surprising that such a proposal would come from someone representing one of the biggest tobacco states in the nation. Once you consider the factors that go into McConnell’s choice, however, it’s not so surprising.

There is, of course, a positive health factor in raising the minimum age. Many point to the public health benefit as their primary reason for support of the idea. The nicotine in tobacco is about as addictive as any other drug out there, and toxins, carcinogens and poisons inhaled and chewed by tobacco users kill hundreds of thousands prematurely every year. Younger brains are more susceptible to addiction, and thus, it makes sense to limit teens’ exposure to addictive substances — especially harmful ones that can kill you.

McConnell has said he decided to push the legislation because of scary spikes in the number of teens using e-cigarettes, which also contain startling levels of nicotine. But McConnell is a calculating political tactician first. We doubt the health factor is as big a driver for him as it is for others.

There’s been a considerable reduction in the number of tobacco farmers and the scale of the industry in Kentucky in recent years, meaning tobacco farmers have less political clout than they used to. Meanwhile, improving public health outcomes has strong public support.

With a reelection campaign around the corner for McConnell, the legislation is undoubtedly as much a move to help his chances in 2020 as anything else.

McConnell’s proposal also has support from big tobacco companies, including Altria, which also owns part of Juul, the most popular e-cigarette company among teens, according to Al Cross with The Rural Blog.

McConnell’s national “T-21” legislation would extend the minimum age requirement to 21 for e-cigarette products, as well.

Altria’s position seems strategic: “Raising the legal age will reduce the pressure for rules limiting flavorings, advertising and so on,” Cross wrote.

What the T-21 legislation represents is an opening bid in a negotiation — a negotiation over how much leeway tobacco and e-cigarette companies should be given to market their drugs and turn profits off people addicted to their products.

No good negotiator takes the first offer put on the table. The first offer is always the other side’s dream scenario — a maximum benefit for them, a minimum benefit for you.

Public outcry over companies making money by selling flavored addiction juice to kids has forced those companies and their supporters to the table.

National T-21 legislation is their dream scenario.

The legal age to buy e-cigarette products is already 18, so the law extends that prohibition by three years.

In exchange for those three years, they want to be free to make their products as addictive and enticing as possible, including in ways that might appeal to minors.

There are kids — young kids well below the age of 18, some not even teens yet — using e-cigarettes.

The 18-year-old age restriction hasn’t stopped them now; why would 21 stop them?

We love the cultural message T-21 legislation sends, at least. There’s no doubt raising the age for tobacco and nicotine to the same age we use for alcohol can have some good effects.

But changing the legal age by itself is a mostly empty gesture that will have limited real-world impact.

In the worst case, it would provide cover for companies in the business of marketing addiction to kids.

Health advocates should applaud McConnell for bringing up the issue and being willing to pass national legislation.

But they shouldn’t fall for the gimmick of the initial offer.

“That’s a fantastic starting point,” they should tell him. “Now what else are we going to add to make sure we accomplish something good?”