DAVID Cameron made good on his pledge not to indulge in "Punch and Judy" politics yesterday - but still showed he is capable of delivering a powerful blow.

In 30 electrifying minutes in the Commons, the new Conservative leader discomforted Tony Blair more than his many predecessors had managed in years of trying.

Messrs Hague, Duncan Smith and Howard would all have mounted an over-the-top attack at deafening volume, probably over Budget black holes and the EU rebate "betrayal".

Instead, Mr Cameron's quiet strategy was to kill with kindness, sympathising with the prime minister that Labour backbenchers bitterly oppose his plans to give schools more freedoms.

"There is no need to worry," the Tory leader soothed. "I'll help you achieve your dreams before you retire, even if your own side are determined to ruin it for you."

It was as if Mr Cameron was throwing a lasso across the chamber to rescue Mr Blair and drag him to safety on the Conservative side where he could, at last, be a true Tory.

Mr Cameron was in the driving seat from the moment he got to his feet to say: "The first issue the Prime Minister and I have to work together on is . . ."

There were Tory cheers as he slapped down Labour's chief whip Hilary Armstrong, for heckling as if she was at, well, a Punch and Judy show, accusing her of "shouting like a child".

Mrs Armstrong, the Durham North West MP, immediately turned the colour of the bright pink jacket she wears to stand out from the ranks of men in grey suits.

Suddenly, Mr Blair was apologising, first for failing to congratulate Mr Cameron on his election success and then for jabbing his finger at him as if spoiling for a pub brawl.

They were minor indiscretions, but revealing nonetheless. Here, at last, was an opponent the Prime Minister was struggling to pin down, unsure of his points of weakness.

As Mr Cameron gently taunted that the Prime Minister "was the future once", Mr Blair must have winced for a decade ago, when his brow was similarly unfurrowed and his hair had lustre.

When the Tory leader switched to the issue of climate change, pledging binding greenhouse gas targets, it was another effective fresh approach, one likely to appeal to younger voters.

It is many years to the next election, more than enough time for the inexperienced Mr Cameron to stumble and even fall, but there were frowns on Labour faces yesterday.

They weren't the only ones frowning. Will the Commons be much fun for us political hacks without the Punch and Judy show?