What does it say about American culture that “Hostel,” the No. 1 movie in the country last week, is about sexually sadistic torturing and killing?

By itself, that particular film-financial factoid isn’t so big a deal, but the reality of American society behind it isn’t encouraging: It can’t be a good sign that the old story of the damsel in distress, rescued at the last minute, has been changed into that of a damsel being bloodied, mutilated and then killed. That trend deserves some comment – and maybe a little backlash.

Variety described “Hostel” as “unhinged gruesomeness.” Director Eli Roth told Salon.com that he got the idea for the movie from a Thai Web site that purported to offer an online pay-for-kill experience. He said there were “guys out there who are bored with doing drugs” and bedding prostitutes. “Nothing touches them anymore, so they start looking for the ultimate high. Paying to kill someone, to torture them.”

OK, but what’s the social impact of such a movie? Will such a cinematic depiction convince some viewers that it’s “normal” to have such thoughts? Will some be encouraged to copy what they see on celluloid?

And what of the larger social impact? The Web site horrormovies.ca observes: “It is merciless with the torture, the violence, & the sex. I guarantee you will walk out of this film trusting no one.” That is, “Hostel” will make you hostile.

But what can’t be debated is the reality of the film’s success. It made $20 million in its first week, beating out such box-office rivals as “Chronicles of Narnia” and “King Kong.” Even the august Financial Times took note of “Hostel” on the front page of its Tuesday “Companies and Markets” section: ” ‘Hostel’s‘ popularity represents a remarkable return on investment for a venture that cost just $5M to make, and may point the way forward for Hollywood as it frets over a third consecutive year of declining ticket sales.”

In other words, get ready for more such blood-sodden fodder – on top of such recent films as “The Devil’s Rejects,” a remake of “The Texas Chainsaw Massacre,” “Saw” (as in saw off one’s limbs) and, of course, “Saw II.”

Those who wish to minimize the socio-cultural significance of these movies might argue that there’s nothing new about stalker-slasher movies, that the ultra-gross-out genre goes as far back as “Night of the Living Dead,” released in 1968. But the trend toward the careful and patient depiction of torture and mutilation, which began with “Reservoir Dogs” in 1992, has been accelerating in recent years.

Others might argue that it’s impossible to get too worked up over movies these days because they are just a small portion of the nationwide entertainment budget. That’s true enough, although it might be noted that the video game industry, which has eclipsed Hollywood in terms of dollars, has also eclipsed Hollywood in terms of violence.

Finally, some will insist that there’s nothing new about violence in the public square. After all, in the long-ago past, the world witnessed such cruel spectacles as gladiatorial combats and public executions – and not just “clean” killings by, say, hanging, but such ritualistic death techniques as drawing and quartering.

And that’s all true. But, for all the barbarism of the past, there were, at the same time, powerful and prevalent cultural antidotes. Romances of knighthood and chivalry, for instance, summoned impressionable young people to uphold values such as restraint and, if necessary, sacrifice to a higher cause.

A new film, “Tristan & Isolde,” which opened Friday, seeks to revive that spirit. The Tristan story – a love triangle in which Beauty yields to Duty – has inspired great art through the ages, most notably Richard Wagner’s 1859 opera. Alas, the new movie will not likely be part of any future artistic pantheon.

But at least “Tristan” tries. Unlike many movies these days, “Tristan” doesn’t seek to profit from the gleeful depiction of human beings being tortured and slaughtered.