My father likes to tell a story about the men living on the railroad tracks where he grew up in central Connecticut. When he was boy, he often rode the tracks on his bike and came across what he thought were “hobos” along the way.

He was surprised when my grandfather, a World War II Army veteran of the Battle of the Bulge, ruefully told him they were veterans. In essence, they never came home from the war, he told his son, a child of the New Frontier who had grown up on John Wayne celluloid depictions of the war, snug in the can-do image of boom and fortitude reflected in the monochromatic images provided by Hollywood and Madison Avenue. There was no room for misfits or traumatized veterans in this American Dream. So they were easily marginalized and forgotten by society, at least in our town, there on the tracks.

As it turns out, not only were they not alone, but there were big hospitals (or in old-fashioned speak, sanitariums) for the thousands of men who returned from World War II with what the old timers called “shell shock” and we know now as Post-Traumatic Stress Disorder. That there was a high rate of “psychotic neurosis” among those vets is no surprise considering the scope and violence of the war, which claimed some 500,000 American lives. That society had nearly airbrushed them out of our contemporary understanding of post-World War II American life is extraordinary.

There are numerous reasons why these hospitals and their patients may not be widely known to us today. One is plain censorship, as in the case of the 1946 documentary “Let there be Light,” which was commissioned by the U.S. Army Signal Corps in 1946. The film, directed by powerhouse director John Huston (who was then a major in the Corps) and beautifully photographed by a team led by Stanley Cortez, followed 75 returning World War II vets suffering “psychotic neurosis” from the war.

Their conditions manifested in such maladies as stuttering, nervous tics, paralysis, amnesia, and social phobias, leading them to an 8-week stint in one of these huge Army hospitals. Huston and his crew had done such a wonderful job of drilling down 75 hours of interviews between the Army psychiatrists and their patients — exposing at a rare level (at least at that time) the pain, the sense of isolation, guilt, and melancholy these men brought home from them the war — that the Army simply banned “Let There Be Light” and kept it from public view for the next 30 years.

The Army was so frightened that the film would hurt recruitment that when Huston tried to screen it for his friends at the Museum of Modern Art in New York City, a couple of military police came and seized it, supposedly on the pretense that the film would violate the privacy of the vets involved. The War Department claimed the releases signed by the men had been lost, but the Army never attempted to get new ones. In Huston’s words:

We then pointed out that, though the film indeed represented a deeply personal investigation into the innermost lives of these men, nothing was disclosed which might cause them to be ashamed. We proposed asking them individually to write letters of clearance, but the War Department said no. The authorities had made up their minds.

So the documentary was locked up in a vault, along with some of the most truthful reflections of the war and the human psyche captured on film up to that time.

“Let There Be Light” was at last released in 1980, but it was in such poor shape that many reviewers scoffed. Plus, they had “The Deer Hunter” and “Coming Home,” and PTSD just was just getting its official due, so everyone knew about head trips and neuroses. What did they care about some grainy 35 mm film whose dialogue you could barely hear over the crackles and pops of the bad audio?

That all changed this month, thanks to the National Film Preservation Foundation, which lovingly restored both the picture and the audio of Huston’s poignant documentary — narrated by his father, actor Walter Huston — and is streaming it now for free on its website, www.filmpreservation.org.

In the film notes, Huston, who went on later to direct such classics as “The Red Badge of Courage” and “The Treasure of the Sierra Madre,” described his work like this:

I visited a number of Army hospitals during the research phase, and finally settled on Mason General Hospital on Long Island as the best place to make the picture. It was the biggest in the East, and the officers and doctors there were the most sympathetic and willing…. The hospital admitted two groups of 75 patients each week, and the goal was to restore these men physically, mentally and emotionally within six to eight weeks, to the point where they could be returned to civilian life in as good condition—or almost as good—as when they came into the Army…. I decided that the best way to make the film was to follow one group through from the day of their arrival until their discharge…. When the patients arrived, they were in various conditions of emotional distress. Some had tics; some were paralyzed; one in ten was psychotic. Most of them fell into the general designation of ‘anxiety neurosis.’…. [Charles] Kaufman and I wrote the script as the picture was shot, which, I think, is the ideal way to make a documentary…. [The purpose] was to show how men who suffered mental damage in the service should not be written off but could be helped by psychiatric treatment…. The original idea was that the film be shown to those who would be able to give employment in industry, to reassure them that the men discharged under this section were not insane, but were employable, as trustworthy as anyone.

Reviewers have called it noir, but that doesn’t necessarily mean this is classic noir in the gritty literary sense, and if you are looking for some John Cassavetes-style cinema verite circa 1966 then this is not the place. Remember, this was commissioned by the Army in 1946. Aside from the first-time use of unscripted interviews and exchanges among the vets and their psychiatrists (a technique that was indeed adopted and broadened by Cassavetes and others years later) the documentary tracks with the postwar ethos, in the sense that the highlighted veterans are eventually cured of their ills and readied to reintegrate back into the hopeful conventionality of American society. The film is accompanied by that breezy 1940s music we associate with screwball comedies of the time, nothing ominous or foreboding as we might expect today.

But it is nearly staggering because the fears and angst of these men are no different from those of the hundreds of thousands who are suffering from the same problems today, from our current wars. If the snooty reviewers from 1980 were were able to get past the poor quality of the film, they might have recognized that if trauma had been dealt with more openly and honestly after World War II — no censorship, no spin — the country might have been better prepared to deal with the problem when our Vietnam veterans returned the way they did in the 1970s.

Apparently, according to film notes, the Army was so upset by Huston’s film that they commissioned another one, but this time with actors reading a script, which hewed closely to the vignettes in the original but sanitized them along the way. It was laughable and seemed “to be less a remake of ‘Let There Be Light’ than an argument against it.”

Many of us spend Memorial Day and Veterans Day and even the Fourth of July watching war movies. These movies are generally prescribed from a modern canon of approved films, and are repeated often. You know what they are. Last weekend’s schedule of movies listed over at American Movie Classics offers the best example: “A Bridge Too Far,” “Patton,” “Flags of Our Fathers,” “To Hell and Back,” “The Dirty Dozen,” “The Green Berets.” Classics.

The media and the government have done their best to shape the lens through which we see war and its effects on the men and women who fight it. Huston’s film bucked that, and for doing so was banned. Now we have a chance to see it, and maybe in a little way “Let There Be Light” will serve as an opportunity to start questioning the cliches, if not our collective understanding, of post-World War II America.