The common phrase, that something is like “rearranging the deck chairs on the Titanic” is often taken to mean “putting one’s effort where it won’t do good”, but it has another, slightly more subtle meaning: futility. (I’m writing this post because a friend was so used to the first meaning he hadn’t thought about the second, and what one man has done, another might do.)

Once the Titanic has been hit by the iceberg, there are two reasons why it doesn’t matter how the deck chairs are arranged:

1. No one is going to sit on them while the boat is sinking.
2. Once the boat sicks, their arrangement will be destroyed by the water washing the deck chairs away from the deck.

Rearranging the deck chairs on the titanic, therefore, suggests an activity is not only secondary to one’s primary concern but moreover one doomed to have no effect whatever.

You can see this by contrasting the Titanic, which sank, to a ship lost at sea where the rations have run out and the crew is starving. Rearranging the deck chairs will not give them food, but they might still take comfort sitting on them in a better arrangement, and whoever eventually finds the empty ship could take advantage of a particularly well thought out arrangement of the deck chairs which has remained after its first crew can no longer use them. (In theory, though admittedly not likely in practice.)