 Complete the following phrase:  The first years of his reign, from 1556 to 1566, Philip II was concerned principally with Muslim allies of the Turks, based in Tripoli and Algiers, the bases from which North African Muslim forces under the corsair Dragut preyed upon Christian shipping. In 1560, a Spanish-led Christian fleet was sent to recapture Tripoli captured by Spain in 1510, but the fleet was destroyed by the Ottomans at the 