In Washington, the former head of FEMA, Michael Brown, defended his agency’s response to Hurricane Katrina and laid much of the blame on what he described as the dysfunctional state and local governments in Louisiana. Brown appeared before a Congressional hearing on Tuesday that was largely boycotted by Democrats who are seeking an independent probe. Brown also said FEMA’s response was hurt by the Bush administration’s focus on the so-called war on terror at the expense of domestic emergency operations. Brown said FEMA was short 500 people in an organization of about 2,500.