Waste deep in the big muddy
And the big fool said to push on. Pete Seeger's 1967 song was a metaphor for Lyndon Johnson and the Vietnam War. It is now shorthand for a blind escalating commitment to a lost cause.
A good example of a blind escalating commitment to a lost cause: the Kemper County Lignite Plant under construction by Mississippi Power. On April 2 its Southern Company parent announced another construction (and startup) write-off of $177 million in its 8K SEC filing. This brings the total cost for the experimental plant to $5.5 billion and counting.