The problem as I see it is that everything which is "wasteful" in government is there precisely because it has a political constituency.
As long as there are more votes and K Street money for what is "wasteful" than there are against it, the waste and inefficiency will remain.
Much government waste is due to bureaucracies which are self serving. Agencies have a perverse incentive to grow larger rather than more efficient. Many factors contribute to this, including the mandate to spend every dime allocated every year. Woe to the agency that returns unspent money to the public purse on September 30.