Time, which, according to the proverb, fears the Pyramids, may be developing a new phobia: Madonna. The 50-year-old pop star has returned to the United States with a new tour, which, according to The New York Times, brings her closer to "her core: careerist ambition and a combative tenacity." Madonna's performance is a feat of aerobic endurance. "There she was, 50 be damned, strutting, pushing her dancers around, even doing double-Dutch jump-rope steps without a tangle." The tour's political overtones may be a bit heavy-handed—a photo montage contrasts McCain with Hitler and Obama with Gandhi—but that isn't scaring off the fans: All four of the Material Girl's performances at Madison Square Garden this week have sold out.