The "mistake" to which Lindsey Graham refers has been in the Constitution since... erm.. well, the Bill of Rights. Without it, the possibility of someone born here legally but not given citizenship for some arbitrary reason exists.
Lindsay Graham proposes to keep some Gitmo prisoners "indefinitely." This is a guy who is a lawyer, for chrissakes. We can't do that even under basic international law of the Geneva Conventions. Something better has to be done than this.