DAVID Cameron could never hope to compete with Boris Johnson as a crowd-pleaser – so he was wise not to try.

The Mayor of London is the great entertainer of politics: funny, engaging, and increasingly popular. Even his opponents find it hard to dislike him.

At the Conservative Party conference yesterday, the Prime Minister presented a deliberate contrast. Yes, there were one or two lighter moments but, overall, it was a low-key, serious and, at times, moving speech with an emphasis on family values.

It is one thing for mid-term polls to suggest that the party would be given an election boost by BoJo – the clownlike nickname Mr Johnson has acquired.

But it would be quite another to actually vote for him to be the leader of the country. When it comes to choosing a prime minister, it does not come down to someone who makes us laugh. It comes down to someone we can trust with the most serious issues.

Mr Johnson is good for London, good for the country, and good for the Conservative Party because politics needs characters. He makes our sides ache when he gets stuck on zip wires at the Olympics and trapped in lifts before important engagements, but would we really trust him with the health service or representing Britain on the world stage in times of crisis?

Whatever we may think about David Cameron’s austerity drive, he is a respected political operator with an authority which Boris Johnson could never match – any more than the Prime Minister could hope to compete with the Mayor of London’s refreshing ability to cheer us up.