For: nihilistic existentialism, moral confusion, and a distorted representation of Christianity
High Noon has all the meaningfulness of the Charge of the Light Brigade, and all the insight into humanity of a carnival mirror, bookended by a western ballad and an unhappy ending, with the upside that the angst-ridden events occur over almost exactly the same amount of time the audience was intended to spend enduring them vicariously. Classic High Noon may be, but true and worthwhile it is not.
Nihilistic Existentialism
The movie ends with the villain Frank Miller lying dead in the street, and the hero Marshal Kane throwing down his badge in the dirt. Kane turns his back—literally, on the ungrateful people he has twice saved from a ruthless killer; figuratively, on all the work he did to save them the first time around. When the movie ends, Kane and his new bride are not heading off to a good life, first and foremost. First and foremost, they are leaving behind years of wasted effort. High Noon ends with the message that, as vital as the conflict with Frank Miller was, and as necessary as it was for Marshal Kane to stay and perform his duty, it was all meaningless in the long run.
Moral Confusion
High Noon is built around a generally socialist view of reality, consistently portraying marriage, family and business in an unbiblical, inaccurate way.
Marshal Kane's duty compels him to stay and fight the villain, and the uncertain outcome decides his new bride on leaving him… possibly forever. He appeals to her on emotional grounds, but neither of them are portrayed as considering their marriage vows morally binding. In High Noon, marriage is meaningful only in a sentimental way, and only until the first conflict arises.
The businesses of the town in High Noon are portrayed as having thrived under Frank Miller's corrupt generosity, and having done poorly ever since, to the point where the business owners are disturbingly pleased at the idea of Marshal Kane being defeated or even killed. In High Noon, whoever runs the businesses has everyone else at his mercy, or, to put it another way, power corrupts, money is power, and business is money.
Family men are portrayed as willing to do whatever it takes to stay out of the conflict, and unwilling to stand up for what is right, or to even change the status quo, for fear of leaving their families without a provider. In High Noon, a family is a moral hindrance, rather than a moral impetus.
A Distorted Representation of Christianity
In High Noon, Christians are portrayed as harsh, ungrateful and self-serving, while Christian pastors are portrayed as weak, incompetent hypocrites.
High Noon takes place on a Sunday morning, when all of the faithful Christians are in church, oblivious to everything that is going on until Kane walks in to gather a posse. Kane is stopped cold and treated as an outcast before he can get anyone to listen to him, and when they do listen, the congregation is torn between gratitude and ingratitude for Kane's efforts on their behalf, with ingratitude winning out in the end. Kane admits to not having been a church-going man, and says, "maybe that's a bad thing," but through scene after scene of cowardice, division, bickering, accusing and ultimately unmoved "Christians", High Noon's obvious insinuation is that staying away from church was not a bad thing. A scene involves a series of images of all the people who left Kane to die, with the church people being compared, not contrasted, with the villains in the saloon.
The only Christian in High Noon who does not take part in the backbiting and debate over Kane's stand against the villain is the pastor, who is portrayed as a complete failure in leadership and apologetics. Kane asks the pastor to influence his congregation toward fighting alongside him, but the man quietly declines, on the grounds that he does not know which course is the right one. The pastor goes on to bring up the "Thou shalt not kill" passage in scripture, and, shaking his head, draws attention to the fact that "we" Christians nevertheless hire lawmen to kill for us, clearly implying that this is in conflict with scripture, and yet clearly implying that this apparent violation of scriptural command is necessary. He ends by shaking his head again and saying, "I just don't know." In High Noon, the pastor has no influence and no answers, and is scripted as having a Holy Book he is unwilling or unable to abide by.
Ultimately, the Christians are all portrayed as being the moral equivalent to the non-Christians. Their relationship with Christ (and, by implication, Christ) is portrayed as hollow and meaningless when put to the test.