The game of chicken involves driving head on towards your opponent, as they do the same, and the loser is the one who swerves out of the way first. If neither swerves, then both lose in a much bigger sense. I was reminded of this as Michael Howard was trotting out the usual arguments for Brexit on the Today programme this morning

Howard argued that a trade deal with the EU would still happen, bringing us continued access to the Single Market, because it is in their interests. He even suggested that following a vote to leave, the rump EU should have another chance to make us a better offer that could be put to a second referendum – rather than, you know, respecting the stated will of the people to leave.

The way this argument normally progresses is that the outers say that we have a trade deficit with the EU, so they will want to maintain trade more than we do, then the inners say that our trade is 50% with them and theirs only 10% with us, so we will want it more than they do, then the outers say that Germany will still want to sell us their BMWs…

This is all dangerously close to missing the point. Trade benefits both sides; the single market benefits both sides. And when an agreement benefits both sides there is always the temptation to demand more favourable terms because the deal will still be in the interests of the other side and so they ought to agree. This leads to a game of chicken (or brinkmanship) with all the risks that implies. The Greek crisis has seen this, with a reasonable reform and bailout package being resisted on both sides in the hope that this will bring something with either more reform or more bailout. Greece has even resisted reforms that are in her interests in order to have leverage, and the election of Syriza – self-destructive as that appears – can be reasonably understood as a final, unsuccessful attempt at brinkmanship. Greece needed the agreement more than Germany did but still didn’t swerve.

Successful agreements are more likely when both parties are willing to follow the same rules and split the benefits reasonably. Any attempt to demand the lion’s share of the benefits will and should be resisted by others because if a country gains a reputation for caving in negotiations, this will cost it more than any single lost agreement. The significance of Cameron’s #EURef deal is that despite this, it bends the rules in our favour. And we still have the rebate on top. No wonder the fear among EU heads of government is of ‘contagion’ – of member after member demanding similar special treatment.

Howard’s case is that we can forego our access to the single market by right, and gain access on better terms by negotiating all over again, with the other 27 heads of government, only one of which wants to sell us BMWs. Maybe they will all swerve before we do; but maybe Malta or Latvia or Belgium won’t. Maybe Greece will hold out as leverage against Germany. And all 27 will know that it is in our interests to have access to the single market even on less favourable terms than we have it at the moment, so, y’know, let’s not swerve just yet.

Do we really want to go there? It is not enough to recognise that our participation the single market is very much in the interests of the whole of the EU, you need to understand the game theory of the process you are going to invoke.