WASHINGTON (AP) - The U.S. prepared to launch a missile attack on Libyan air defenses, but American ships and aircraft stationed in and around the Mediterranean Sea did not participate in initial French air missions Saturday, according to two U.S. officials familiar with the unfolding intervention. One official said the U.S. intends to limit its involvement - at least in the initial stages - to helping protect French and other air missions by taking out Libyan air defenses. An attack against those defenses with Navy sea-launched Tomahawk cruise missiles was planned for later Saturday, one official said. Both officials spoke...