True, but there is an explicit exit clause for leaving the EU as a whole.
Well, there is a decision by the german constitutional court approving the overall mechanism of the ESM while recognaizing that for the bail out mechanism there is ultimately no escape possible form the ESM ,meaning even when a state exits the EU and the euro zone, this state still has certain obligations deriving from that.
This is something no particually democratic, binding coming generations for ever. Moreover, the right to exit the EU was only granted in 2007 by the treaty of Lisbon , alias the EU constitution.
Note that the European Constitution was rejected even though some member states voted overwhelmingly in favor of its adoption in referenda, but it was ultimately scrapped because two member states did not ratify it.
The point is, the EU-constitution and the Lisbon treaty is ultimately quite similiar. There are many features from the constitution, which was twice rejected, in the treaty. So, it of course gives the impression that it is kind of a backroom policy making. Another reason why the EU is so unpopular.
You do realise that these were decisions of the national governments, don't you? So in essence what you are saying here is that giving power to national governments conflicts with self-determination.
No, I am not saying this. However, when a institution is so deeply unpopular then it does conflict with democracy that states hand over power against the wishes of the people to an entity like the EU.
As for the specific treaties that govern the EU, all of them need to be ratified by each and every single member state, and there is no requirement in international law that mandates referenda for treaty ratification.
That may be so. However then politicans must have the guts to clearly communicate that they want the project of the EU even against the wishes of their people or that the will of the people is not important in this regard.
Furthermore, we are now reaching such a high degree of integration that national constitutions need to be changed in order to be coherent with the EU regulations, automatically triggering binding refrendums in many states, such like Germany.