NEW : President Obama calls the denigration of Vietnam veterans a `` national shame '' `` America will be there for you , '' he said in his speech to Congress on Tuesday. Memorial Day launches a 13-year commemoration of the Vietnam War 's 50th anniversary . Obama lays a wreath to the fallen at Arlington National Cemetery .
NEW : President Obama calls the denigration of Vietnam veterans a `` national shame '' `` America will be there for you , '' Obama tells veterans and their families . Memorial Day launches a 13-year commemoration of the Vietnam War 's 50th anniversary . Obama lays a wreath to the fallen at Arlington National Cemetery .