How a Deadly Strike Hit an Elementary School in Iran

A continuing military investigation has determined that the United States is responsible for a strike that hit an elementary school in Iran, according to U.S. officials and others familiar with the preliminary findings. Iranian officials have said the death toll was at least 175 people, most of them children. Malachy Browne and Julian E. Barnes, who have been covering the strike, discuss what probably led to one of the most devastating military errors in decades.