How does one enforce such a suspension, without resorting to prison? (I suspect someone will mention "fines/monetary penalties", but that's rather begging the question.)
Yes, and when you don't pay your fine and drive without a license, and society decides it cares because children, you go to prison. This is what I meant. Now you're in prison, the overall rate of drunk driving is unaffected, and America is still the prison champion of the history of Earth, which was the point of the thread.