Based on your comment, I did get the point because this is exactly what I was talking about. Does the visa state "this visa is irrevocable, you will never have

Based on your comment, I did get the point because this is exactly what I was talking about. Does the visa state "this visa is irrevocable, you will never have to do anything to be allowed to stay in the country, until the end of times, ever, we promise."? Maybe it does, and then I'm happy to be wrong. In politics and legislation, there is no "promises", no "indefinite". Laws are the reflection of what society wants at a certain point in time - at least in functioning democracies. For everything, not just immigration. I'm not saying it doesn't suck. I've had my fair share of dealing with immigration regulations and I know how awful it is, but it is foolish to think that a right to residency will never be questioned and subject to different rules. Only citizenship is definite.