Other people have sovereignty too. And they too may choose to “take back control” of things you would rather they didn’t.

The sovereigntist argument for Brexit, which was one powerful element of the referendum campaign – taking back control of laws, borders and money – is a perfectly legitimate case to make.

If you think the consequences of living in a bloc where the pooling of sovereignty has gone well beyond the technical regulatory domain into huge areas of public life are intolerable for democratic legitimacy and accountability, that is a more than honourable position.

But others who have chosen to pool their sovereignty in ways and to extents which make you feel uncomfortable with the whole direction of the project, have done so because they believe pooling ENHANCES their sovereignty – in the sense of adding to their “power of agency” in a world order in which modestly sized nation states have relatively little say, rather than diminishing it.

They did not want that pooling to stop at the purely technical trade and regulatory domain.

Brexit advocates may think this is fundamental historical error, and has led to overreach by the questionably accountable supranational institutions of their club. They may think that it leads to legislation, opaquely agreed by often unknown legislators, which unduly favours heavyweight incumbent lobbyists.

Fine. There is some justice in plenty of this critique.

Then leave the club. But you cannot, in the act of leaving it, expect the club fundamentally to redesign its founding principles to suit you and to share its sovereignty with you when it still suits you, and to dilute their agency in so doing.

It simply is not going to. We see this exceptionalism, with the idea that deep mutual recognition agreements should be offered to the U.K., alone of all “third countries” with which the EU deals, and in the initial propositions on both financial services, other services and data.

We see it in the constant have your cake and eat it demands which run through every document the European Research Group produce or endorse.

If by sovereignty we must mean more than purely nominal decision-making power and we mean something about the genuine projection of the UK’s power in a world, then, as we get into the deeper trade, economic and security negotiations ahead, we are going to need a far more serious national debate about trade-offs.

And the trade-offs are real and difficult. No-one should pretend that all the answers will be great.

To take just one technical example, though it rapidly develops a national security as well as an economic dimension, cross border data flows are completely central to free trade and prosperity – not that you would know it from listening to our current trade debate, which remains bizarrely obsessed with tariffs which, outside agriculture, have become a very modest element in the real barriers to cross border trade.

The EU here is a global player – a global rule maker – able and willing effectively to impose its values, rules and standards extraterritorially.

Before the referendum, we had Brexit-supporting senior Ministers and advisers who should have known better, fantasising about the autonomy we would have to plough our own furrow once sovereignty had been resumed and we were no longer obliged to live under the jackboot of the General Data Protection Regulation (GDPR).

Sobriety only started to set in in this debate after the referendum, as the implications of a failure on the UK’s part to achieve a so-called “adequacy determination” under GDPR from the EU started to sink in – because corporates across a huge range of sectors started to set them out for Ministers.

The same applies to so-called “equivalence decisions” in masses of financial sector legislation. Again, the consequences of failure to achieve such decisions will be the substantial erosion of market access into EU markets by U.K. companies.

What, really, are these “equivalence” and “adequacy” stories about? They are the EU projecting power – it does so quite as well as, probably more effectively than, Washington, in multiple critical regulatory areas – and using its pooling of internal sovereignty to impose its values and standards well beyond its borders.

The current U.K. debate on sovereignty leaves so many corporate players mystified and cold because in “taking back control” over our laws and leaving the adjudication and enforcement machinery of what used to be our “home” market, we are privileging notional autonomy over law- making over real power to set the rules by which in practice we shall be governed, since departure from norms set by others when we are not in the room will in practice greatly constrain our room for manoeuvre.

 The massive costs of deviation will force large scale compliance with rules set when we are not part of setting them