I remember the day David Cameron walked in to the House of Commons in 2001. We had just lost the general election and I thought: "Here at least is someone who can offer some hope for the future." I knew him already from our time working together for Norman Lamont and I knew that a serious talent had just arrived.

In the decade and a half since then he has been a huge asset to this country and to our politics. His Parliamentary career has been highly unusual: out of 15 years in the Commons, he has spent 11 of them leading his party. No other leader of modern times has spent such a large proportion of their parliamentary tenure at the absolute top of the political tree.