Trillion
Of course, the fact that the trillion dollar number is a thundering load of bat guano will never come into this conversation.
How many other government programs could withstand applying every possible peripheral effect and tallying it up?
Just one example off the top of my head: One of the things added on for that trillion was lost investment potential. Has anybody figured out what Social Security really costs if you add up what the economic effect would have been of people investing trillions in retirement funds in the private sector for the past seventy years?