Is there discrimination, in all directions? Yup. The world is a tribal place.
But you should move on from that "tiered" thing. I live here. I have been doing a project with Arabs for the last two weeks. We have lunch together most days. Move on.
- Constitution -- You clearly have not read the constitutions of Syria, Saudi Arabia, or many other countries. Ethnic groups are all over the identities of most of the world's countries.
- Automatic citizenship - How narrow do you define this? African Americans can go to Liberia and other countries of Africa. Until just twenty years ago or so anyone with a German grandparent could automatically get German citizenship. If you are Cuban you can get American citizenship. Are you thinking this through?
- NPT, I am not sure anyone cares, but this is very different than your other topics.