THE FIRST SALVOS have been fired in a trade war that is unlike any other. Not that all has been peace and quiet on the trade front until now. Opposition to the Central America Free Trade Agreement (CAFTA) by America’s inefficient but politically potent sugar beet producers and apparel makers has delayed congressional approval. Bob Zoellick, who negotiated that agreement before moving up to the number two spot in the State Department, is confident that opposition will be overcome, but at the moment it is a close-run thing.