Formally: Jeb!
Informally: Jebland
Dialectical variant of English: Jeblish
Collective name for the people of Jebland: Jebanese

I’m kidding of course. We all know the process to rename the U.S. would be taken over by the wealthy and we’d wind up named HCH (Human Capital Holdings), LLC, a shell corporation/nation that is jointly owned by Blackrock, Vanguard, and State Street.