There's one possible effect of Brexit that I suspect hasn't had the consideration it merits - the opportunity cost.

What I mean is that all of us - politicians, journalists and regular folk - have limited attention and mental resources. Attention devoted to Brexit is therefore attention that's taken away from other matters. And given that state capacity is also limited, if our best civil servants are working on Brexit (which is an if) then they are not focusing on other policies. Brexit steals cognitive bandwidth.

For example, in a better world, we'd devote our political attention to overcoming secular stagnation, welfare reform, combating inequalities of power and income, improving workers' rights and so on. As it is, attention is focused on trade deals, our relationship with the single market, countless treaty renegotiations and so on - all of which are efforts merely to avoid losses, something which could have been more simply achieved by a Remain vote. Rather than turn our attention to progress, we're wearing ourselves out trying to avoid regress.

Brexit distorts the policy agenda in other ways. For example, industrial policy should be concerned with increasing productivity and innovation. But in fact, it's focused upon limiting the damage of Brexit, perhaps by offering handouts to favoured big firms whilst letting smaller ones swivel in the wind.

And then there's the question of the values promoted by the Brexit debate. Brexit fuels nativism and even perhaps mercantilism, whilst the policies it squeezes out would focus instead upon more enlightened ideals such as liberty and equality.

All this, however, poses the question: is there really an opportunity cost here at all? Might there instead be an opportunity benefit?

All the above assumes that we are on a kind of policy production possibility frontier, so that Brexit means less good policies or administration elsewhere. But what if we are in fact well inside the frontier? Then Brexit - far from being a barrier to good policy elsewhere - might actually help it.

For example, had we not had Brexit Cameron and Osborne would still be in office so we'd be stuck with fiscal austerity. As it is, their departure has created space for a "reset" of policy. If Johnson and Fox were not tied up with Brexit negotiations, they'd probably find some ways to damage our polity. And a government whose energies and political capital weren't sapped by Brexit might well have even more ability to hurt the worst off.

Which brings me to a paradox. We lefties can be quite relaxed about the opportunity cost of Brexit. Yes, Brexit is regrettable, but it has the silver lining of distracting the Tories from doing damage elsewhere. Tory supporters, however, have no such comfort. They should regard Brexit as a distraction of government energy which could be well-employed elsewhere. In this sense, it is intelligent Tories who should most regret Brexit.