There are a number of things that I don't want the EU to interfere with, but regulations that already exist should be respected. Otherwise, what's the point?
There were two cases over 40 years ago versus the Dutch and Italian governments when they raised import tarrifs and nationalized an energy company respectively - both were blatant violations of a treaty they signed voluntarily and of the regulations that resulted from it. If national governments were given unlimited freedom to abandon agreements they've previously entered, then the EU would be the useless institution it's often made out to be.
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