One of the latest acts of government regulation intended to save us all from ourselves is the growing number of states raising the minimum age to purchase tobacco or vaping products to 21. As CBS News reports, Illinois is among the latest to make this move.

It’s a nationwide push. More states are raising the legal age to buy tobacco and vaping products from 18 to 21.

It’s in response to what some health officials are calling a public health crisis.

Illinois has joined New Jersey and six other states in raising the age limit. While statistics show tobacco continues to lose its appeal for young people, vaping is skyrocketing among middle and high school students.

Now here comes the kicker. Last week, Congressman Robert Aderholt (R) of Alabama’s 4th District introduced legislation that would make 21 the legal age for tobacco or vaping products for the entire country. On the surface, you might find this an appealing idea. After all, you don’t want more young people taking up smoking or becoming addicted to nicotine, right? What’s not to like?

But there are two questions we need to be asking here. First of all, is this truly a federal matter? Where does the federal government derive the power to push this level of regulation on the states? The states still set the minimum age for other things, particularly marriage, as their citizens see fit. The same goes for driver’s licenses and other government “permission slips.”

But there’s an even bigger question that ties into all of these regulations, including the purchase of alcohol or tobacco. We’ve long held that there is an understanding in America that below some given age you are considered a child and not entirely responsible for all of your own actions and the consequences thereof. Beyond that age, barring any serious impairment, you are an adult and are responsible for the decision you make as well as being entitled to all of the things that come with adulthood.

With that in mind, consider the following proposal: If you are not old enough to buy alcohol, tobacco or vaping products, you are not an adult because you can’t be trusted to make those decisions. But if you are not old enough to be considered an adult, then you are not old enough to marry, fight and die for your country or vote. (Or drive, for that matter.)

In response to the first question above, I would have to say that these are issues for the states to resolve for themselves in most cases. (There’s an argument to be made that minimum age for military service or voting in national elections is a federal issue.) So perhaps we wind up with potentially fifty different minimum ages defining adulthood. But inside each state, how do we justify saying that you’re “an adult” at sixteen when you want to drive a car, but you’re a child until 18 if you want to get married or vote? And then you go back to being a child for three more years if you wish to have a beer or light up a cigarette?

The point is, a little consistency would be nice… at least on a state-by-state basis. The current system appears nonsensical.