Betrayed by their hero, Cameron's eurosceptics are quickly returning to their bitter, angry roots.
By Alex Stevenson Follow @alex__stevenson
The last time David Cameron updated the Commons on his return from Brussels he was treated like a hero. The acclaim appeared to have no limits; the prodigal son, had he seen this display of lionising, must have felt like a big disappointment upon his own return. What a difference a follow-up summit makes. Today the Tory eurosceptics edged away from the PM, collectively wrinkling their noses as if he had made a bad smell.
Labour had anticipated this, and so had lined up a stratagem of their own to increase the discomfort. The opposition's jibes began even before Ed Miliband stood up to respond to Cameron's statement. When the prime minister told MPs that he had "vetoed that treaty" they exploded with laughter.
The comedy threshold is always lower in parliament, of course, but this was nowhere near funny in the normal sense of amusement that you or I might understand. No, this was political laughter. As every single Labour MP screaming their head off knows, it is the kind used when its target is to be mocked into submission. Cameron's discomfort was obvious under this barrage of rolling-in-the-aisles hilarity.
The frontbench was unusually deserted: George Osborne, chewing the cud, and Ken Clarke, arms folded and trying not to nod when Miliband made his points, had much more room to spread out than they are accustomed to. A garishly-tied Nick Clegg kept silent vigil to the prime minister's right - until, with the PM still speaking, he got up and strode out of the chamber. This did not pass unnoticed by the opposition. "Bye!" they waved frantically. Cameron gave them a grudging half-smile in response.
At the bar of the House stood David Miliband, thoughtfully watching his brother's efforts with a faint smile on his face. 'There but for the grace of the unions,' he may have been thinking. But on this occasion he could not have done better than his younger brother, who is always at his best when on this kind of exuberant form.
We discovered, he told MPs, that Cameron thinks "a treaty is not just for life, it's just for Christmas!" Cameron and Osborne protested when Miliband insisted that, despite the PM's veto, an EU treaty had been agreed to. "There isn't one!" Cameron shouted across the despatch box, mouth smiling, eyes glinting. Miliband's response was unusually strong for the leader of the opposition: "It talks like an EU treaty, it walks like an EU treaty - it IS an EU treaty!" The Labour backbenchers gave a loud cheer with plenty of bass.
At least Cameron could engage with Miliband. His backbenchers were a very different kettle of EU-quota fish. Cameron did his best to lift them. It was a measure of his desperation that he was forced to resort to the sort of theatrics most often seen elsewhere in its nearest real-life equivalent - the pantomime. He got them chanting "nothing!" repeatedly at the opposition. He exaggeratedly turned around when Miliband suggested they didn't believe a word he said, prompting their own exaggerated denials. Methinks the government benches doth protest too much.
Their grumpiness was best summed up by Mark Reckless, who icily asked Cameron: "Can the prime minister explain what it is he's vetoed?" The PM did his best, but this was a tough crowd. He did not experience the antagonism of old, that sense of comfortable, reassuring hostility. Nor was it the hero-worship of last month. Instead the atmosphere on the government benches appeared one of frustrated disappointment: like a band whose latest album was a huge let-down, Cameron had deflated them. Their disillusionment was palpable.