Of the big horror movies of the '70s, you have 'The Omen,' 'The Sentinel,' 'Rosemary's Baby,' 'The Stepford Wives,' 'Burnt Offerings' - these are all romantic fatalist movies where there's a sort of glimmer of hope... but darkness wins.
We have been taught to regard a representative of the people as a sentinel on the watch-tower of liberty.
The eyes like sentinel occupy the highest place in the body.
Conscience is the sentinel of virtue.