A British army Challenger tank pulls security during a decisive action training environment exercise, Saber Junction 2012, at the Joint Multinational Readiness Center in Hohenfels, Germany, Oct. 24, 2012. Saber Junction 2012, the U.S. Army Europe's premier training event, is a large-scale, joint, multinational, military exercise involving thousands of personnel from 19 different nations and hundreds of military aircrafts and vehicles. It is the largest exercise of its kind that U.S. Army Europe has conducted in more than 20 years.