Tony Blair suffered his first defeat ever in Parliament this afternoon. He has said in the past that he would step down as Prime Minister if he lost a vote in the Commons, and during the last week as this highly contentious vote over the Terror Bill loomed, commentators have raised that prospect repeatedly. At the moment, it does not look like Blair will allow this vote to force him to resign. Yet the politics of this situation have been developing rapidly during the last week, and the fallout probably will continue.

There are many reasons why Blair's fate matters a good deal to the US. His political defeat today bodes ill for George Bush.