WASHINGTON (CNN) -- Frustrated by a lack of progress in rebuilding the state's levees, a Louisiana Democrat threatened Wednesday to block President Bush's appointments requiring Senate confirmation until "significant progress" is made toward restoring the flood protection damaged by Hurricane Katrina in August. Saying coastal residents "cannot wait much longer," Sen. Mary Landrieu blamed the loss of 1,200 lives in her home state "to the loss of wetlands as a protection and a lack of levees that held." She is demanding that the Bush administration develop a comprehensive levee, flood control and coastal restoration program, and dole out the funds...