In this week's NS politics column , Conservative MP Jesse Norman insists that Tory MPs remain "remarkably united, not divided, over the EU issue". But everything we're hearing suggests that the reverse is true. Iain Duncan Smith is reported to have had "an extraordinary stand-up row" with chief whip Patrick McLoughlin, warning him that he will resign  if he is ever forced to vote against his eurosceptic principles again. "If you ever put me in this position again, that's it," he said.
The truth is that the Tories are as divided over Europe as ever, it's just the nature of the division that has changed. The divide used to be between the europhiles (Michael Heseltine, Ken Clarke, Chris Patten, Ian Gilmour, Geoffrey Howe et al) and the eurosceptics (everybody else) but it's now between the eurosceptics and the eurofanatics.
There is no easy way to heal this division. Duncan Smith was reportedly "extremely unimpressed" with Cameron's handling of the issue but it's hard to see how a one-line whip or a free vote would have helped matters. Indeed, without a three-line whip, the rebellion would likely have been even larger. As Lord Ashcroft  noted yesterday:
Others have blamed "party management", as though imposing only a one-line whip and allowing many more Tory MPs to cast an apparently cost-free vote for the referendum motion would not have created even bigger problems (and led to just as many complaints about "party management", no doubt from the same people).
ConservativeHome's Tim Montgomerie  has suggested that a referendum on EU membership is the only way of "bringing closure" to the decades-long split in the party. But would the eurosceptics really go quietly if the vote went against them? After all, despite a 67 per cent vote in favour of EEC membership in the 1975 referendum , Labour still called for withdrawal in its 1983 manifesto.