In two prior posts, I’ve agreed with influential blogger Morgan Downey that the proposal in Puerto Rico to fine the parents of obese children is a bad idea, and that the food environment has a great deal to do with the globesity crisis.

But I balked at the implication that parents don’t have primary responsibility for obese children. I wouldn’t have said so before 5 or 10 years ago — because I didn’t get it — but now it’s clear: incorporating fitness and nutrition into children’s worldview is a basic ingredient of child protection.

If fines aren’t the right tack, though, what can be done collectively? I usually fail, but I’ll try to be brief. Clearly, the basic choices are to act or not to act.

The argument against acting begins with the position that how one parents is a matter of personal choice. We allow exceptions — we make rules on what sort of physical contact with children is OK, for example, and jail those who cross the line — but in general, these issues often define the fault lines of freedom.

A corollary is that laws against ads directed at children, for example, are protected by the First Amendment, and so far, the body politic has chosen to give the free-speech rights of corporations higher priority than child-protection concerns.

The argument for acting is that the globesity epidemic is real, and has real implications we cannot collectively ignore. The easy example is public health, where it is estimated that we spent $190 billion on obesity-related health care costs in 2005. But there are many implications, even including national security, according to a couple hundred retired generals, admirals, and other officers. Yes, one’s an estimate, and one’s based on (collective) opinion, but doesn’t it make sense that a general lack of fitness, easily observable all around us, is going to have potentially bad consequences?

I look at all the ways in which we’ve collectively decided that strictures on individual conduct are justified — speed limits, pollution standards, crying fire in a crowded theater — and I conclude that we will be better off if the clearly present danger is collectively addressed. We have decades of real-world evidence showing what results if we keep on doing what we're doing.