Mark, “a nation of immigrants” may derive from the effort to pass a piece of legislation, but that is meaningless except as a cutesy ah-ha debating point. Billions of phrases are introduced in politics in hopes of catching the public imagination. When one does, it’s not because of the source of the phrase but its resonance. “A nation of immigrants” caught on because it speaks to something very deep in the American character and experience — Mark Steyn’s seven generations of New Hampshire-ites notwithstanding.