Saletan thinks this proposal might have legs:
"Three years ago, I thought the movement to legislate against junk food was politically futile. But that was before the successful assaults on trans fats, calorie counts, and opening fast-food restaurants. Those victories, apparently, were just the appetizers. The next course is behavior modification through taxation. And this article is the recipe."
There is really no debate that drinking soda ("pop" if you prefer) is not healthy. Humans love it, as evolutionist David Sloan Wilson explains in his book Evolution for Everyone, because we are "dancing with ghosts." Once upon a time in our evolutionary history, sugars and fats (which we need, just not in large amounts) were not readily available. Presumably, to crave them was incentive to seek them out. Now that we can have sugar and fat whenever we want, to crave them is to be "dancing with ghosts."
Meanwhile, we keep getting fatter and fatter, and spending more and more of the healthcare dollar on obesity-related medical conditions. Can a soda tax make a dent?