"But there is much more to it all. It needs to be emphasised at the start that the establishment of a single currency in the EC would indeed bring to an end the sovereignty of its component nations and their power to take independent action on major issues. As Mr Tim Congdon has argued very cogently, the power to issue its own money, to make drafts on its own central bank, is the main thing which defines national independence. If a country gives up or loses this power, it acquires the status of a local authority or colony. Local authorities and regions obviously cannot devalue. But they also lose the power to finance deficits through money creation while other methods of raising finance are subject to central regulation. Nor can they change interest rates. As local authorities possess none of the instruments of macro-economic policy, their political choice is confined to relatively minor matters of emphasis – a bit more education here, a bit less infrastructure there. I think that when Jacques Delors lays new emphasis on the principle of ‘subsidiarity’, he is really only telling us we will be allowed to make decisions about a larger number of relatively unimportant matters than we might previously have supposed. Perhaps he will let us have curly cucumbers after all. Big deal!"
https://www.lrb.co.uk/the-paper/v14/n19/wynne-godley/maastri...