Because citizens are stakeholders in their government. Everyone else is not. Naturalized citizens earn their citizenship through a well defined process [1].

[1] https://www.usa.gov/become-us-citizen#item-36212

> The decision to apply is a significant one. Citizenship offers many benefits and equally important responsibilities. By applying, you are demonstrating your commitment to this country and our form of government.

> Support and defend the Constitution. Stay informed of the issues affecting your community. Participate in the democratic process. Respect and obey federal, state, and local laws. Respect the rights, beliefs, and opinions of others. Participate in your local community. Pay income and other taxes honestly, and on time, to federal, state, and local authorities. Serve on a jury when called upon. Defend the country if the need should arise.

https://www.uscis.gov/citizenship/learners/citizenship-right...

"Earning" citizenship has nothing to do with your own choices. It depends on your country of origin and the American public's openly racist opinions about the relative merit of people from your country. It's a given that any immigrant wants to become a US citizen, but quotas deny them that chance.

This is just like the NIMBYs. Work to deny people the opportunity to become "stakeholders," then use your success in doing so to claim their needs don't matter.

The birth lottery is a poor indicator of deservingness. This behavior, on the other hand, is bright-as-day proof of its absence.

How so? Because citizens can vote? Because citizens have some legal protections that don't apply to non-citizens? Doesn't that mean that non-citizens actually have more of a stake in the competence and behavior of the government because they have much more to lose from certain government actions?

I'm unsure how we can argue this any further. You're arguing "what supports the existence of the concept of citizenship and a sovereign nation". That is the legal framework (across nations) we've agreed upon.

Culture, history, belief in a common set of values or traditions - Tradition.

People ought to have a vested interest in the place they work, and live. I know of no better way to do that than citizenship.

I have no inherent problem with the concept of citizenship, I just point out that it is arbitrary, and more importantly, I don’t think it should be the threshold for the people the government should be expected to protect or support.

It is arbitrary, because you have to draw the line somewhere.

How about people who are not violent criminals and don’t have contagious diseases? That is far less arbitrary.