Tory backbenchers were delighted by David Cameron

PMQs verdict: Miliband’s smile froze on his lips

PMQs verdict: Miliband’s smile froze on his lips

The smiles quickly faded. Ed Miliband thought he was on to a winner – but somehow the Labour leader missed yet another opportunity to make David Cameron look stupid.

It was, make no doubt about it, a great choice of topic. Energy company SSE's decision to implement a price freeze set up a superb opening gambit for Miliband. Did Cameron think this development was, as the prime minister had said of Labour's price freeze proposal, "unworkable, impossible to implement and probably a communist plot?"

The Labour narrative of Cameron being a stooge for energy bosses fits very well into the opposition's attempts to paint the PM as in hock with the barons of big business. "He's not the prime minister at all," as Miliband put it. "He's the PR man for the energy companies!"

This was great politics. What undermined it was the policy.

As SSE had pointed out, it was the government's changes to the energy companies obligation which made this two-year price freeze possible. There was an obvious counter to this – that 500 jobs are on the line and several offshore wind farms have also been shelved to make the price freeze possible. But Miliband wasn't able to talk about those, because doing so would have talked down his own price freeze plan.

He should have had a more robust response to Cameron's boasts about the coalition reducing energy bills than simply pointing out this is inaccurate (they're actually rising at double the rate of inflation). "What's weak," Miliband shot across to the heckling Tory backbenches, "is not standing up to the energy companies!"

This gave Cameron an opportunity to broaden his defence away from the specifics of the price freeze and instead go on the offensive. "They shout support at him in here," Cameron said of the Labour MPs yelling behind their leader, "and they go brief against him outside!" The delighted grins with which Miliband and Ed Balls had greeted Cameron's opening remarks had completely disappeared. Poor old Ed shot a look of pure venom across the despatch boxes. He knew where this was heading.

What Cameron was doing – and what he proceeded to do for much of the second half of the main exchanges – was remind everyone present what a hellish week the leader of the opposition has had.

It even prompted the prime minister to be uncharacteristically grandiose. "Their vote against the Budget," he said of Labour, "will go down in the history of this parliament as a massive own goal by Labour." That level of pomposity is rather rare from Dave, who usually prefers bullying jibes more appropriate to the playground. Perhaps it was a response to Miliband going unexpectedly downmarket.

"Calm down dear, calm down," the Labour leader had urged Cameron. This was an echo of the PM's now infamous sexist jibe against vocal Labour frontbenchers. Heads turned in the press gallery as Miliband pressed on: "Or should I say for the benefit of the chancellor, eyes down dear, eyes down." Was this sexist too, everyone wondered briefly – until we realised it couldn't possibly be, as everyone involved was of the same gender. Ahem.

How had it come to this? Having kicked off with what seemed like a ripsnorter of an opening, Miliband's price freeze politicking was fizzling out. His final conclusion – that Cameron "will always stand up for the wrong people" – just wasn't strong enough to get the opposition backbenches roaring their approval. Cameron, by contrast, ended with a withering jibe. Miliband, he said, was "a man with no plan and, increasingly, no future".

It was not quite Cameron's "he was the future once" knockout blow against Tony Blair – but it was close.