falling on Tony Blair's sword

Clare Short is so mid-Atlantic. The British Secretary of State for International Development first criticized her government's rush to war and threatened to resign from office (this definitely not the way of an American politician) and then she decided to stay, apparently convinced she needs the job and the job couldn't be done without her (definitely an American attitude). She was convinced that the war as planned was wrong, but now believes that only she can help reassemble the country upon which she is about to rain death and destruction.

In an interview for the BBC its political editor Andrew Marr suggested,

So the difference between you and Robin Cook, essentially is that you feel that you have an absolutely vital job in government still to do involving Iraq.
Robin Cook, Labor leader of the UK House of Commons, actually did quit yesterday.