I believe it is not always legal to have vote after vote until the government decides it's got what it wanted.

The goverment of a country can make anything it like legal or illegal. That's what being a sovereign state means. It is also a cause of opposition to the EU. It is taking decisions that would normally be taken by European countries, and not always deciding the same way they would. If that's not surplanting national sovereignty, what is?


Of course, if a country far enough outside international norms, and doesn't have a currently useful goverment, or nuclear weapons, then the UN/US/anyone else who feels like sticking their nose in might invade, but that's another story...