Rearranging the deck chairs on the Titanic means making well-meaning but negligible adjustments to an endeavor that is doomed to fail. It is a useful phrase, but it has been overused.
The expression goes back at least three decades (the earliest example we could find is from 1975), but its use has picked up sharply during the last few years. You know an expression has worn out its welcome when politicians take to it—for example:
Palin derided the GOP “establishment” and accused them of simply rearranging “the deck chairs on a sinking Titanic.” [Alaska Dispatch]
“Some [cutting] is better than nothing, but we see it as rearranging deck chairs on the Titanic,” said Chip Tarbutton, president of the Roanoke Tea Party. [Washington Post]
Democratic leaders compared the Republican budget measure to “rearranging the deck chairs on the Titanic” and said it would cost far more in the long-term than it saves in the short-term. [San Antonio Express]