President Obama made an unannounced visit to Dover Air Force Base today to be on hand as the coffins of 30 US troops were carried off a plane, reports USA Today. The ceremony was closed to the press. The troops, many of them members of an elite Navy SEALS unit, were killed in a helicopter crash in Afghanistan over the weekend, and Obama was to meet privately with their families today. NATO thinks a Taliban rocket likely brought down the chopper. (More President Obama stories.)