It's striking to me that the polling reveals quite high support among Americans for some kind of government-run back-up, if private insurance is unaffordable. Here's the NYT poll showing 65 percent support for several months and only 26 percent opposition. The WSJ poll, while framing the issue more negatively, also finds a plurality of support and only a minority firmly opposed.

I should come off the fence here.

It seems to me that a public option which allows the government to use its huge buying power to achieve cost cuts that no private company could manage would be a Trojan horse. But a government option forbidden to use such leverage, but allowed to have an edge from administrative and overhead savings, is a useful compromise. It's one more incentive for cost control. The question is: what kind of public option? And what are the limits of its structural advantages?

Obama has pledged that any public option would be of the kind I could support. So why am I not yet reassured entirely?