Whatever the merits of Michael Winterbottom’s “Road to Guantanamo,” and they are several, it is undoubtedly an effort to hinder and obstruct the Bush administration’s war on terrorism. It is important to understand this at the outset because that effort’s success or lack thereof depends on the film’s effectiveness at disguising its motives – and it seems very effective to me.

The film pretends to be about the sad story of four young men of Pakistani descent from Tipton, near Birmingham, England. It begins with a dramatization of events in October 2001. Ruhel (Farhad Harun), Shafiq (Riz Ahmed), Asif (Arfan Usman), and Monir (Waqar Siddiqui) travel together to Pakistan from England because Asif’s family has arranged a marriage for him there, a common occurrence in the Anglo-Pakistani community.

On a whim, the four decide to take a side trip to Afghanistan just in time to be caught up in the civil war between the Taliban and the Northern Alliance, aided by elements of the American armed forces. Monir disappears, never to be heard from again. Ruhel, Shafiq, and Asif are identified as Taliban fighters and interned at Camp X-Ray, Guantanamo.

There, they suffer hardships and harsh treatment amounting at times to what some would describe as torture. They are put in isolation cells, subjected to loud noises, and placed in “stress positions”; there are also stray punches and slaps and, in one case, where one of the prisoners is supposed to be insane, a severe beating. At another point, an American guard is seen desecrating a Koran.

We have only the men’s own testimony that any of these things actually happened. But the film is a conduit for that testimony and makes no attempt to evaluate it or assess its reliability. It shows them bravely and defiantly enduring it all, always insisting on their innocence of any connections with the Taliban or terrorism and finally, slightly more than two years later, their release on the grounds of lack of evidence.

Mr. Winterbottom (“Wonderland,” “In This World,” “9 Songs”) is a talented filmmaker who, co-directing here with Mat Whitecross, masks the propaganda beneath this compelling human story. He mixes interviews with the three survivors, now inevitably known as “the Tipton three,” with a running dramatization of their experiences in Pakistan, Afghanistan, and Cuba.

Every now and then he cuts away to glimpses of the larger war on terror in vignettes – such as a speech by President Bush on Guantanamo in which he says that “one thing we do know: These are bad people” – rendered deeply ironic by their context.

In fact, Mr. Bush’s announcement must have included an unspoken qualification such as “so far as we know” or “the overwhelming majority,” as well as understanding that rounding up terrorist suspects on the basis of the limited knowledge we are bound to have of organized terror operations is almost guaranteed to sweep in some innocents along with the guilty.

That’s if they are innocent. I must say that the three men’s story sounds a bit thin to me. They were in Pakistan for a wedding and just decided one day to take a trip up to Afghanistan where they were “basically just chilling out”? They could hardly have been unaware that American warplanes were bombing the hell out of the place at the time, yet they just wanted to play tourist?

But say they are innocent. That fact doesn’t tell us anything about the hundreds of others caught in the same dragnet, let alone whether the acts of terrorism that must have been prevented by their incarceration made it worthwhile to risk imprisoning the odd innocent man.

The film ignores all such questions in its focus on the three innocents and subsequent attempts to suggest that the other internees are as likely to be innocent as the three protagonists here.

Mr. Winterbottom doesn’t just show that it’s unfortunate that these men were imprisoned at Guantanamo or even that it was wrong for America, not knowing of their innocence, to imprison them. He implies that it is wrong for America to imprison anyone, guilty or innocent, at Guantanamo – which just happens to be the view of the increasingly vocal anti-war and anti-Bush left.

Those who recognize that we are at war, and that dedicated terrorists are looking for opportunities to kill innocent Americans, are likely to think differently. If we have good reasons for suspecting certain foreigners of plotting murder and mayhem against us, on what moral or prudential grounds are we told that we must do nothing but wait until they have killed more Americans – by which time they may have blown themselves up anyway?

At the critics’ screening I attended in Washington, D.C., there were “peace” activists openly recruiting demonstrators against the Guantanamo prisons. Their presence only confirmed my impression that “The Road to Guantanamo” never bothered to make any pretense of being anything but propaganda.

In this it is like Vice President Gore’s “An Inconvenient Truth” or Michael Moore’s “Fahrenheit 9/11.” All three movies are made with the assumption that anyone who watches them will already be in sympathy with their aims, so they make no apology for blatant partisanship – nor any attempt to be judicious or evenhanded with their material.

“The Road to Guantanamo” is highly watchable, as can be expected from Mr.Winterbottom, and would be an absorbing tale if it were pure fiction. As it is, however, viewers should be aware that the real-life subjects have an agenda, as does the film itself, which subtly alters our response to a human story that would otherwise be simply enthralling.

jbowman@nysun.com