The trade of queens
After a nuclear explosion in Washington, D.C., kills the president, a dissident faction of the Clan from an alternate universe joins a faction of the U.S. government in a political takeover. There is no safe place for a pregnant Queen Miriam and her Clan except, perhaps, in the third alternate world, New Britain--which has just had a revolution and a nuclear incident of its own.
Fiction, Nuclear weapons in fiction, Clans, Clans in fiction, Nuclear weapons