You, dear reader, have the advantage over me. I am writing this Sunday, before the election takes place. The opportunities for me to look foolish are legion. So I will resist both predictions and triumphalism. For months, though, I’ve been assessing President Bush’s vulnerability, but win or lose, it is important to acknowledge the daunting challenge Sen. John Kerry faces. Republicans have been spinning this fact for months and they are right. First, we simply do not defeat an incumbent president in wartime. After wars surely, but never in their midst. Republicans have been spinning this fact for months, and...