David Cameron delivered an hour and ten minutes of David Cameron yesterday: my strengths and weaknesses. This was not so much a party address as a job application. He even told us what he had done at university. But the speech also had the ingredient without which no address will work — it had a real argument. His strengths, he said, were his values — sound money and low taxes. His priorities, he explained, would be driven by his faith — in family, community and country. His qualification for office, he suggested, was his character — steely by way of sunny.

But perhaps the most impressive sections were those in which he took on his perceived weaknesses. Mr Cameron had the confidence to pose the case against him much as his opponents would have done. He deftly turned back the accusation that he is a novice. He claimed for himself the prospect of progress against an experience that has, he alleged, ended in failure.

The speech was long, it was lacking the urgency of last year’s address to the Conservative conference and it had little by way of rhetorical flourish. But it was a speech that hit the right sombre note: he said nothing substantive that was new, but he promised a substantial change. He talked squarely about the difficult economic times ahead, about reining in an expansive State and taking unpopular decisions that will restore the health of public finances. His pitch for the top job was formidable enough that it answered the one question he really posed: can you imagine me as prime minister?

But this very success will bring with it greater scrutiny. For all the personal polish of Mr Cameron’s speech, both his party and his policies seemed curiously absent. In a passage that more than tipped the hat to Tony Blair, Mr Cameron commended his party for having had the courage to change. It was less clear in the hall that the delegates had changed quite as much as he suggested. The rapture that greeted his lines on the Union, on health and safety, and on the dependency culture stood in contrast to the village cricket match applause for the rehabilitation of prisoners and becoming the party of the NHS. But, all the same, the red meat to the faithful and the sheer confidence of the delivery meant Mr Cameron was able to get his party to applaud lines on social justice and on the causes of crime that hardly rank among their usual priorities.

Perhaps it is most charitable to say that the Conservative party is not unchanged but it is still unclear. This is because the Conservatives remain a fearful party, so accustomed to losing that they are now afraid to upset the electorate by laying out policy in detail or confronting choices in concrete terms.

If Mr Cameron does turn out to be the change that the country wants, then the country needs to know more about the nature of that change. His vision of a broken society is still wrong-headed, but, even allowing for the slogan, his means of addressing failing communities, violent crime and family breakdown are vague. His commitment to the Armed Forces is reassuring, but how will the Conservatives match their rhetoric on defence with the reality that the “cupboard is bare”? When healthcare inflation is running at 7 per cent annually in the developed world, it is difficult to know how to reconcile Mr Cameron as a “fiscal conservative” and his claim that the Tories are now “the party of the NHS”.

Much remains unclear about the party that Mr Cameron leads. The nature of his putative government will need to be subjected to a more searching light, and will receive it. But if he went on for ten minutes too long, then his audience and the country had better get used to it. The British people are set to hear a great deal more from Mr Cameron.