There is palpable confidence in the Tory party that David Cameron will still be prime minister after the general election. It flows not from any surge in public enthusiasm for the idea of Conservative government, but from a lack of evidence that voters are ready to trust Ed Miliband with power.  That view is corroborated by demoralisation on the Labour benches. When Tory veterans look across the floor of the Commons they see miserable reflections of their former selves in the wilderness years, under William Hague, Iain Duncan Smith and Michael Howard.  Related: Johnson urges Cameron to bring forward vote on EU membership to 2016  But as a second term in government comes into focus for the Tories, it also brings another spectre from the past: the civil war over Europe, deferral of which has been a defining feature of Cameron’s leadership. The promise to hold a referendum on Britain’s membership of the EU has been a modest success. It has not suffocated Ukip, nor even stopped Tory MPs defecting to Nigel Farage’s side. But it has comforted others with the illusion of agreeing on something about which they disagree. The vote may one day rip the Conservative party in half, but on the question of whether that day should come they are strangely united.  As a tool for party management the referendum’s utility expires in May, two-and-a-half years before the deadline Cameron has set himself for holding the vote. It is hard to imagine a less auspicious genesis for a government policy. The first thing the newly returned prime minister would have to do is start planning for something that is also the last thing he wants to spend his time doing. He would have to renegotiate the terms of Britain’s EU membership, knowing that there is no deal that could satisfy the militant sceptics. Other member states have more important things to do than help Cameron in his quest for a formula that somehow severs and preserves Britain’s ties to Brussels at the same time.  Cameron says the reforms he envisages require treaty revisions. That cannot happen before the crisis in the eurozone has been stabilised, which may take years. Meanwhile, Vladimir Putin is stress-testing European solidarity via war in Ukraine. In the past month, jihadi terrorism has struck in Paris and Copenhagen – a borderless threat to which national governments cannot respond in isolation. In that context there is not much pan-European appetite for a special treaty negotiation only Britain wants. Cameron looks like the man who sees his neighbour’s house on fire and comes round to claim items that were borrowed years ago.  The new terms of EU membership on the referendum ballot paper will be vague assurances and draft compromises – a “post-dated cheque” as the diplomats say. This will neatly fit the sceptics’ pre-prepared account of Brussels as a capital of conspiracy and deception.  Cameron is like the man who sees his neighbour’s house on fire and claims back borrowed items   So the battle lines of a referendum campaign in 2017 would not be so different to one held sooner, which is why some Downing Street advisors would like to bring the thing forward to 2016. The later it is left, the more depleted will be Cameron’s stock of political capital and the likelier it becomes that Britain flounces out of the EU in a spasm of mid-term, anti-government protest.  The same calculation is influencing big business, much of which does not like the idea of the referendum but believes it has to happen. That is one reason why Labour’s reluctance to have the vote isn’t paying out in terms of vocal corporate backing. Many bosses calculate that their interests are best served by accepting Cameron as PM, having the blasted plebiscite, and bankrolling the “in” campaign. But they’d want the deal sealed quickly.  Except it wouldn’t be sealed; not any more than the Scottish independence vote settled that question. Ukip and its fellow travellers in the Tory party would not lay down their weapons. Already the conditions are there for a losing “out” campaign to rebuild itself as a nationalist revanche, denouncing the result as inauthentic, a product of media bias and an establishment stitch-up, not the true will of the people.  Those are all reasons why Miliband has not promised his own EU vote, despite pressure from within his party. The Labour leader war-gamed the scenarios with his advisors and saw that a referendum conceived in tactical expediency would be misshapen from the outset. It would devour ministerial time and energy, stoking social division and creating economic uncertainty. It would sabotage European diplomacy, erecting barriers of resentment between Britain and its partners as they grapple with epoch-defining challenges.  And all without neutralising militant Euroscepticism. It would defer a few problems while spawning new ones like Hydra’s heads. It would be a monster beyond the control of its creator, roaming the political landscape, spitting poison into debate, ravaging the government’s agenda.  The alternative view is that the prospect of an EU vote has been dangled in front of the British electorate and withdrawn too many times, while the European project itself has shifted too far from that to which assent was granted in 1975 for that mandate still to be valid. Permission needs to be renewed. People demand it as their democratic right. Besides, for Cameron the consequences of not promising to have a referendum were unthinkable. He might not have survived long enough to fight a second general election.  But a forced hand is not the same as a good idea. Cameron sees that a referendum is inevitable. Miliband sees it is a nightmare policy that solves nothing. Both can be right.
A vote will spawn so many new headaches for the Tories that they may try to get it over with in 2016