Earlier this month, lawmakers overrode a veto from Gov. Paul LePage to raise the legal age for buying tobacco products in Maine to 21. It had previously been 18.

While advocates for increasing the age focused on data about health and cost savings that could come from the law change, LePage said he vetoed the legislation because 18-year-olds can serve in the military and, perhaps, be killed in a war.

Even after lawmakers from both parties overrode his veto, he continued to vent his anger to the Legislature. In an Aug. 8 letter, he blasted lawmakers for being hypocrites by allowing 18-year-olds to vote and join the military, be tried as adults and to pay taxes.

He also accused them of “social engineering” by banning 18-year-olds from buying a product “that you don’t like.”

LD 1170, which was sponsored by Sen. Paul Davis, a Republican from Sangerville, wasn’t about not liking tobacco. Rather, it aimed to reduce youth smoking. One way to do this is to make it more difficult for high school-age kids to obtain tobacco products. Nine out of 10 smokers started before they were 18, according to the U.S. Surgeon General. Most high school students know plenty of people who are 18 and can buy cigarettes for them; they are less likely to know someone who is 21.

Raising the tobacco purchase age is no cure-all, but it could reduce smoking by 12 percent, the Institute of Medicine concluded, if the policy were adopted nationwide. Although it would take years for the full health effects to be known, the institute’s modeling shows the result would be 223,000 fewer premature deaths and 50,000 fewer lung cancer deaths among those born between 2000 and 2019.

Brain research also supports raising the tobacco purchase age. The prefrontal cortex, the portion of the brain responsible for decisionmaking, is one of the last areas of the brain to fully develop and is still developing during adolescence. That’s one reason car rental companies don’t rent to people under 25 without a lot of extra fees.

LePage is right that there are inconsistencies in laws that determine what Americans can do at what age. Many of these laws are based on a general logic about maturity. Others were enacted, or changed, because of special circumstances, such as the need for more soldiers to serve in the military, especially at times of war.

You can’t be president, for example, until you are at least 35. You can serve in the House of Representatives at 25, but you can’t be a U.S. senator until you reach 30.

There is little historical record of why the framers of the Constitution set these age limits, but they were likely thinking that experience, both in life and politics, would improve the ability to govern.

James Madison, in the Federalist Papers, wrote, “senatorial trust, which, requiring greater extent of information and stability of character requires at the same time that the senator should have reached a period of life most likely to supply these advantages.”

The age at which men had to register for the draft in the U.S. was dropped from 21 to 18 in 1942, when the country had entered World War II and needed a larger pool of potential soldiers. Blacks were not included in the draft until 1943.

As for LePage’s call for Maine legislators to support raising the voting age and age for military enlistment, the voting age is set by the 26th Amendment to the U.S. Constitution and the Pentagon sets military age limits, so Maine lawmakers cannot change them.

The governor’s bluster aside, Maine lawmakers took an important step to reduce smoking by raising the tobacco purchase age.