Maya Moore had four of the United States\' 15 steals Tuesday in a defensive show that put the Americans in the Olympic semifinals with a 91-48 win over Canada. The United States women won their 39th consecutive Olympic basketball game and are seeking their fifth straight gold medal. Canada managed only eight points in the first period and the outcome was never in doubt as the United States set up a semifinal meeting Thursday against either Australia or China. Playing in the first of the day\'s quarterfinal contests, the Americans limited Canada to 16 field goals and 30 percent shooting. Canada turned the ball over 26 times. Diana Taurasi led a balanced American scoring attack with 15 points while Candace Parker and Sylvia Fowles had 12 each. Chelsea Aubry, who scored 10 points, was the only Canadian to reach double figures.