Summary: Three suicide bombers killed 20 people in an attack on a construction firm in southeastern Afghanistan, with the Taliban claiming responsibility for the assault. … The Taliban claimed that it kidnapped 50 Afghan policemen in northeastern Afghanistan — part of the insurgents’ murder and intimidation campaign against anyone affiliated with the U.S.-backed government. … A provincial governor in southern Afghanistan said that seven civilians were accidentally killed when a NATO helicopter fired on two vehicles believed to be carrying Taliban fighters. … One-year retrospective: One year ago today, on March 27, 2010, Aubrey Immelman reported that the U.S. and Russia sealed the first major nuclear weapons treaty in nearly two decades, agreeing to slash the former Cold War rivals’ warhead arsenals by nearly one-third and talking optimistically of eventually ridding the world of nuclear arms altogether.