Sen. Frank Lautenberg died last year at 89 -- an unremarkable event, except for one thing. The New Jersey Democrat was the last surviving World War II veteran in the Senate. Only two remaining House members, John Dingell of Michigan and Ralph Hall of Texas, served during that war, and both are leaving Congress at the end of this year.These departures help explain why the current controversy over outrageous inefficiencies in the Veterans Affairs department has become ammunition for one more partisan battle in Washington.