The passage of US healthcare reform is enormously consequential, and not just for the things the new law aims to affect. The manner of its passage, as much as its substance, makes November’s mid-term elections pivotal. They may decide the political trajectory of the United States for the next several decades. To see why, you must understand the improbability of what has happened. Barack Obama just tore up the US political rulebook. A year ago there were two scenarios for healthcare reform. One was that the Democrats would carry a willing public with them and pass a comprehensive bill. Another...