It took Hollywood 40 years to get around to making a movie about the Titanic ... and even then it was less interested in the disaster per se than in using it as a dramatic backdrop for a typical piece of Tinsel Town melodrama.
Mister Roberts is only half a John Ford movie. Precisely which half has been debated ever since this naval comedy/drama was released in 1955. Ford, the grand old man of movies, was fired from the project halfway through filming.
Donovan’s Reef (1963) is a film of John Ford’s old age. Depending on how you look at it, it's either a gentle reverie or an escape from all the things in real life which were making Ford a cranky old man.