An idea meaning or suggesting: Everyone is born free. Even those suffering oppression and bondage / slavery have a birthright. Soldiers and Wars don't give a nation and its people freedom. But that freedom is inherited as is freewill. Everyone's birthright is that he/ she has the right to: be, not be, believe, disbelieve, accept, reject, think, do, and not do whatever he / she wants to in this mortal life.
synonyms: prerogative, will
Paul: I'm so proud to be American. It's because of all the soldiers that died 200 years ago so I can be free.
Emma: Actually, your birthright is that you're always free to do and think whatever you want until death. If someone transgresses against you and physically keeps you from doing what you want to do, well then, that's their birthright as well.