So, how well will health reform work after it passes? There’s a part of me that can’t believe I’m asking that question. After all, serious health reform has long seemed like an impossible dream. And it could yet go all wrong.

But the teabaggers have come and gone, as have the cries of “death panels” and the demonstrations by Medicare recipients demanding that the government stay out of health care. And reform is still on track. Right now it looks highly likely that Congress will, indeed, send a health care bill to the president’s desk. Then what?

Conservatives insist (and hope) that reform will fail, and that there will be a huge popular backlash. Some progressives worry that they might be right, that the imperfections of reform —...