New York Mayor Michael Bloomberg has gotten a sour reception to his proposal to outlaw the sale, in the Big Apple, of high-sugar drinks larger than 16 ounces. That pint, of course, is now a "small" offering at many fast-food restaurants.

On "The Daily Show," Jon Stewart wondered how the mayor could ignore some of New York's famous culinary delights - particularly the mountains of meat on "sandwiches" at the Carnegie Deli - while targeting the 32-ounce Coke.

Right-wing talking heads appreciated the opportunity to lament the rise of the "nanny state" - Americans, after all, have the inherent right to bear the 40-ounce Slurpy.

As a practical matter, Mr. Bloomberg's proposal faces all sorts of enforcement problems, but the truth is that the man has made a valuable point.

Obesity has emerged as the nation's principal public health problem, eclipsing even smoking as a cause of debilitating and lethal diseases. As a public policy matter, obesity has become a principal driver of health care costs.

Sugar-laden drinks are a legitimate target in fighting obesity. The average American gets about 200 calories a day from sugar-laden drinks. But their even bigger role in the obesity epidemic, according to many studies, is that their highly concentrated starches and sugars promote over-eating.

So, efforts to slow the rise of obesity by limiting the intake of high-sugar drinks make sense.

Regardless of whether Mr. Bloomberg's proposal gets traction, it's clear that a move away from "liquid candy" would improve public health and reduce the national health care bill.