Here is the premise of Paul Howard’s A Nation Once Again, a devastatingly funny and piercingly perceptive novel that unpicks the absurdities in the unity question, among many other absurdities. The four green fields, each one a jewel. The romantic notion of a united Ireland has allowed many to become misty-eyed when balladeering, often late into the night. The romantic, simplistic notion has led to many worse crimes than balladeering as well. Fact-checking offers no counterpoint in these moments as feelings trump facts, but where the facts can’t work as a corrective, maybe an even more powerful force can. These…