A COUPLE of weeks ago, when noting a series of slow catastrophes it's probably too late for America to do anything about (gun control, climate change, etc), I forgot one: obesity. The Centers for Disease Control (CDC) report that 35.7% of Americans are now obese, notes Aaron Carroll in a blog post pithily entitled "My God, we're obese". America has been the fattest country in the world since the start of the OECD's comparative statistics tables, and there's no reason to think that's changed, though Mexico is giving us a run for our money lately.

The CDC report has an interesting breakdown by state, based on survey results, which we highlighted yesterday in our daily chart. (The survey methods were changed in 2011 and can't be compared with prior years; they're based on self-reports, so they come up with total obesity figures lower than the 35.7% figure above, which is based on standardised medical testing.) The states with the highest obesity rates are in the South and Midwest. The lowest obesity rates are in the west and north-east. States like Colorado, California, Massachussetts and New York have rates in the low 20s; states like Mississippi, Texas, Michigan and West Virginia have rates in the 30s.

The CDC estimates obesity-related health care costs $147 billion per year.

I very much doubt America is going to do anything, as a matter of public health policy, that has any appreciable effect on obesity rates in the next couple of decades. It's not that it's impossible for governments to hold down obesity; France, which had rapidly rising childhood obesity early this century, instituted an aggressive set of public-health interventions including school-based food and exercise shifts, nurse assessments of overweight kids, visits to families where overweight kids were identified, and so forth. Their childhood obesity rates stabilised at a fraction of America's. The problem isn't that it's not possible; rather, it's that America is incapable of doing it.

America's national governing ideology is based almost entirely on the assertion of negative rights, with a few exceptions for positive rights and public goods such as universal elementary education, national defence and highways. But it's become increasingly clear over the past decade that the country simply doesn't have the political vocabulary that would allow it to institute effective national programmes to improve eating and exercise habits or culture. A country that can't think of a vision of public life beyond freedom of individual choice, including the individual choice to watch TV and eat a Big Mac, is not going to be able to craft public policies that encourage people to exercise and eat right. We're the fattest country on earth because that's what our political philosophy leads to. We ought to incorporate that into the way we see ourselves; it's certainly the way other countries see us.

On the other hand, it's notable that states where the public has a somewhat broader conception of the public interest, as in the north-east and west, tend to have lower obesity rates. Perhaps federalism will allow some further progress on a state-by-state basis in those states whose political ideologies facilitate action on this front.