They say it is never too early to plan, so here is a brief look at how to bring the country back together in the event of a Remain vote this June.
The government will have a mandate for staying in the EU on David Cameron's terms, but millions of Britons will have voted to leave. The free movement of people will remain in place, but countless politicians will have said migration needs to change. We will be in the single market and Europe's complex decision making system, but the British people will be more alert to the flaws of both.
This alertness should form the basis for our future EU membership: watchful and constructive. Before Ukip linked migration to the idea of the EU in the public imagination, most people vaguely associated Brussels with rules for straight bananas and cheap flights. With the engagement and detailed discussion raised by this referendum, far more people will take a genuine interest in the whole span of EU involvement.
Failure to pay attention to the 45-49% of voters who chose Leave would be a mistake. It would allow them to push for another referendum as soon as possible, just as the Scottish nationalist movement has done. It would allow Ukip to turn itself into a catch-all anti-establishment party, a voice for the disenchanted and the voiceless.
The referendum will have affirmed that EU structures are part of Britain's unwritten constitution. As such, the Brussels institutions deserve and require the same level of scrutiny that parliament and local government get here. Perhaps they deserve more, given the EU's remoteness and intergovernmental nature.
The electorate will have become alive to European issues thanks to the debate stimulated by the referendum. This must continue: our journalists, bloggers, think tankers, the EU scrutiny committee and interested citizens will need to hold the EU to account. It is part of our governance: we should make sure it delivers projects in Britain's interests. We need to keep an eye on the digital single market, scrutinise the final draft of the EU-USA trade agreement TTIP, push for high safety standards for car exhausts. Equally, we need to be ready to fight Eurozone developments we'd rather stay out of, while participating wholeheartedly in those that will stimulate the continental economy. This should ultimately mean there are more European consumers with money in their pockets for British goods and services.
Migration is set to be a key issue in the EU debate, and if we vote Remain, the basic fact of EU free movement will continue. The pro-migrant side (of which I am part) cannot rest on its laurels. It is obvious that many non-racist Britons are worried by the effects of migration on our culture, jobs and public services. The government must get on with its long-delayed migrant dividend following the ideas of British Future, so regions that have seen high migration will see a boost in spending to ensure their services keep pace. State spending on integration measures (p.68) like language tuition, culture classes and workplace standards enforcement all need to be ramped up. The minimum wage has to be universally enforced. This would mean those who come here can fit in easily, and won't be seen as undercutting native workers.
More controversially, the government could explore pushing the EU to its limits. Historically Britain has followed most rules to the letter. Other EU member states ignore rules they dislike for as long as possible, implement them weakly, enforce them with one eye shut, or outright defy them: Germany has broken rules on running a trade surplus for years, for example. We should not oppose every inconvenience just to be a nuisance but when there's a rule whose consequences seem contrary to what Britain agreed, or whose effects are much worse than expected, then we should explore a little creative disobedience. We may eventually be slapped on the wrist by the EU Court of Justice. Equally we may find support from other members and a way to improve the rule. An example might be the steel industry: we should have found ways to support British (and Italian and Dutch) steel as soon as it was concluded that China was dumping at below-market cost.
A big leftwing issue in the referendum is the EU-US deal 'TTIP'. Elsewhere I argue that fear of TTIP is a terrible reason to vote to leave, but that does not mean it is perfect. If we vote Remain then we need to make absolutely sure that the NHS is protected from TTIP and its Canadian equivalent (CETA). Further afield, we need to push for transparency and fairness in deals like the Trade in Services Agreement (TiSA) and the proposed Investment Court System (the replacement for ISDS). Along with this, left wingers should support and encourage Margarethe Vestager, the Competition Commissioner as she goes after tax dodging firms - helping show the EU is not a rampant capitalist conspiracy. Commissioners will be, after all, servants of the British public.
If Remain wins, there are sure to be bruised egos and red eyes. That doesn't mean Britain will stay divided. We can pull together if the victors give credit to Leave's fears and hopes, and take material action to address them.