There are many political reasons why Gordon Brown is able to hold on to his office despite the undoubted ferment over the past few weeks. The power of incumbency, his dominance of the upper echelons of the party, the lack of a clear successor, the openness required by Labour rules to unseat a leader, the desire of Labour MPs to avoid a general election, the need for Labour not to have a second 'unelected' prime minister in one term - all these have played their part. But that most significant, and unpredictable, element of politics, the role of individual personalities, has also been crucial. Nick Robinson outlines "the three extraordinary personal decisions" of Alan Johnson, David Miliband and John Hutton, which have each contributed to Gordon Brown's security in his job.
It is one of the things that makes both politics and history so fascinating - the unpredictable role of the individual.