Former Arizona Cardinals' football player Pat Tillman died in battle in Afghanistan, fighting for the Army Rangers. Tillman Gave up a lucritive football contract to join the military, in response to the attacks of September 11, 2001. In the past, it was much more common for professional athletes to be in the military. During World war two, more than 90 percent of Major League Baseball players who were on prewar rosters served in the armed forces (though a small percentage found themselves in the same battle situations as Pat Tillman). Steve Goldstein speaks with University of Nebraska at Omaha history professor Steven Bullock, whose new book "Playing for their Nation" chronicles professional baseball players who served during world war two.