GM   November 11, Monday, 4.50PM  the city of Algeciras, Cadiz province, Spain   Algeciras is easily one of the world's busiest ports. Connecting the shipping of Africa, the Americas and Europe meant the city was a hive of activity, and the three newcomers from America had seen plenty of evidence of that just from the plane.   Down on the streets that feeling was compounded. The air rang with voices from a dozen nations, the roads hummed with traffic racing across the metropolis, and alon