I'm not clear why free movement of capital could not be restricted at all even with perfect freedom in the other 3 and monetary union (for instance, since there are state subsidies to some companies, the state should be allowed to prevent the company moving its capital as soon as they end). But assuming that it is the case, then why should the 4 freedoms be considered an unqualified good thing to be spread as widely as possible?

Yes, within the EU the main problem is as you describe. But with the UK, that is less relevant as they are not part of the EU. Anyway, I was just pointing out that I had been under the impression that you were no fan of free movement of capital, and thus that you may not necessarily want to expand the 4 freedoms without restraints.

Actually, I'm not that sanguine about total free movement of goods and services if countries are allowed environmental and social dumping (or other externalities). It seems to me that those freedoms can only make sense with a somewhat consistent playing fields (and that means social, ethical, political consistency, if of course not identity). And the UK is often unhelpful in that way.

As an anectode, I remember a UK politician vigorously opposing environmental regulations because "dominant winds blow pollution towards the continent, so we should not spend a penny to fix a problem that is not ours". I thought that was rather blunt.

Earth provides enough to satisfy every man's need, but not every man's greed. Gandhi

At this point freedom of capital is NOT so much of a problem as the refusal to fix the broken monetary union with a fiscal union and a central bank with a sensible mandate including the end of the prohibition of monetary financing.

Is that what you meant?

A lot of this so-called 'freedom of capital' is probably still-legal tax 'avoidance'. Shell companies, dummy offices et al. Better regulation (always stuck at the yapping-about-it phase) would cleanse those stables, which is why it's so soft-pedalled.

'The history of public debt is full of irony. It rarely follows our ideas of order and justice.' Thomas Piketty