This coming Sunday, the Motion Picture Academy will select its winner for Best Documentary. One of the selections, Marshall Curry and Sam Cullman's If a Tree Falls: A Story of the Earth Liberation Front, offers a surprising take on the nature of "terrorism" and unearths the early roots of today's Occupy Movement. The documentary takes viewers inside the world of Daniel McGowan, an environmental activist whose zeal and frustration led him to commit acts that the media came to brand as "eco-terrorism."

If a Tree Falls catches up with McGowan years after he traded in his black mask, ninja duds and gasoline bombs for a sedentary life with a straight job and a supportive family. But when his past catches up with him, McGowan is forced to reflect on the surreal injustice of it all: "No one got hurt and no one was injured but I'm facing life plus 335 years."

If a Tree Falls is a vivid and visceral film that chronicles the birth and fiery path of the Environmental Liberation Front (ELF), a shadowy group of radical activists that predated and prefigured the current generation of Occupiers.

The film's historic footage includes many "where-have-I-seen-that-before" images of people smashing windows and suffering punishing body blows from police truncheons. There is even a scene of a police officer pepper-spraying ranks of peaceful protestors sitting on the ground with their arms linked. (But this was the 1990s and they were "environmental activists," not students, so no paid much heed. If you were an environmental activist, cops were expected to come down on you. It was part of the job description.)

Watching a slightly chubby, stubble-bearded and soft-spoken Daniel McGowan puttering around the house with his family and friends in New York, you would never peg him as the target of "the largest domestic terrorism investigation in the history of the United States." How was it that someone who graduated college to take a job at Burston-Marsteller, wound up on the governments "terrorist" list?

The Radicalization of Daniel McGowan

McGowan's sister Lisa tries to explain how her brother became such a tunnel-vision radical. She recalls coming home one day to find that Danny had stripped all the labels off all her food cans to recycle the paper. When she pointed out that she could no longer tell a soup can from a can of beans, he replied: "Gee, I never thought of that."

For McGowan, it was at the Wetlands, a famous New York City eco-bar, "where it all changed." That's where he saw an environmental film that revealed the brutal reality of logging, mining, and whaling. "Holy crap! What are we doing?" McGowan thought. And, from that point on, he describes himself as living in "a state of perpetual mourning."

He started protesting, wrote hundreds of protest letters and became further radicalized at a Wisconsin Rendezvous. It was the first time McGowan really spent time outdoors. After bonding by skinny-dipping in a lake, everyone went down to the local mining office to protest and got arrested.

McGowan migrated to Oregon and the site of a proposed US Forest Service timber sale. When the locals heard the pristine Warner Creek was to be opened to logging they responded to the news by Occupying the forest. They dug trenches in logging roads and blocked trucks and bulldozers. They built a protest encampment smack in the middle of a road — complete with a walled perimeter and a drawbridge. The Occupation lasted for a year, right through the winter snows. Eventually the USFS bulldozed the encampment and arrested the protesters.

"Soon after," one activist recalls, "things began to escalate." It was becoming increasingly clear that the Forest Service does not exist to "protect forests." It sees forests as crops. A 1,000-year-old old-growth redwood is just a resource to be fed to the logging industry.

The Rising Tide of Green Anger

The ELF decided to underscore this revelation by torchlight. The USFS's Oakridge Ranger Station was the first to go up in flames. This act marked the arrival of an enviro version of the "black bloc" — and it signaled a split in the movement.

Another galvanizing event occurred on June 1, 1997 when the Eugene, Oregon, city council announced plans to cut down a historic "heritage tree" to build a parking lot for Semantec. Eleven activists climbed into the top branches the night before the tree was to be logged. A hearing on the fate of the tree was scheduled the next day but city officials were in no mood to wait. They sent in police equipped with masks, guns and truncheons. The enterprising cops employed cherry pickers that allowed them to assault the activists clinging to the branches 40 feet above the ground.

During the ensuing scuffle, the camera zooms in on Jim Flynn, one of the tree-sitters and a former editor of Earth First! Journal, as an officer in a cherry-picker cuts off one leg of Flynn's pants in order to aim a blast of pepper-spray at his genitals. His legs flailing in obvious pain, Flynn tries desperately to escape the sting of the chemicals without losing his grip on the tree.

Despite the protests, the tree was cut down. This arrogant show of force — in support of a corporation over the wishes of the community — gave rise to an anger that was vast and incrementally radicalizing.

Bob Barton, a logger who also is an environmental activist, offers this observation: "The industry tends to call the environmentalists 'radical' but the reality is that 95% of the standing native forests in the United States have been cut down. It's not 'radical' to try and save the last five percent. What's 'radical' is logging 99 percent."

McGowan, a disgruntled city kid from the East, found himself immersed in the Ancient Forests of the Pacific Coast where the sight of logging trucks and clear cuts was just too painful to ignore. "This is butchery!" McGowan thought. "Why are we being so gentle in our activism when this is what's happening?"

The ELF soon took on another form of butchery: the slaughter of wild horses at the Cavel West meat packing plant in Redmond, Oregon. Local protesters had spent 10 years in a fruitless effort to shut the plant but on July 1, 1997, a squad of ELFers torched the plant and destroyed it. The effectiveness of the action was undeniable. In a single night, ELF had done what a decade of petitions, vigils and letter writing had failed to accomplish.

The same flamboyant tactic was soon being applied to timber companies, Bureau of Land Management buildings, and a nearly finished $12 million ski resort at Vail, Colorado.

Inspired by this new and demonstrably effective form of action, other independent, autonomous and anonymous ELF cells soon began to proliferate across the US setting ablaze corporate assets linked to resource exploitation and biotechnology research.

A spirit of revolution was in the air. An Age of Green Anarchy had dawned. People occupied the forests, threw their bodies in front of roaring logging trucks, climbed onto trucks layered with the lifeless trunks of 500-year-old trees. And banner of Earth First! Rose above the fray: "No Compromise in Defense of Mother Earth."

Police responded to protests with increasing aggression and violence, at one point peeling back the eyelids of nonviolent protestors sitting with their arms locked and using Q-tips to swab pepper-spray directly to their eyes. One screaming girl can be heard howling: "What are you going? I'm just trying to protect the trees!

The growing public anger helped fuel protests at the World Trade Organization meeting in Seattle. Once again, the police over-reacted and triggered riots that shut down the meeting. The WTO demos also saw the arrival of the "black bloc" — roving bands of black-clad anarchists who specialized in causing property damage.

Looking back at these scenes of civil war in the streets of Seattle looks a lot like the more recent battles in the streets of Bahrain, Egypt, and Syria. Members of the NGOs who organized the nonviolent protests against the WTO can be heard railing against the black bloc. "This is not what the demonstration is about. These shopkeepers worked hard for their property!" But the ambivalence of extreme activism is revealed in an exchange with one woman who angrily condemns the anarchist's violence but, when a reporter asks what she thinks of the Boston Tea Party, responds: "I thought it was great!"

Suzanne Savoie, another member of McGowan's ELF cell, succinctly summarizes her firebrand role: "The goal was to send a message that Consumer America is destroying the world."

As McGowan reflects as one point: "I'm not suggesting the path of destruction is the right path," but "when you're screaming at the top of your lungs and no one hears you, what are you supposed to do?"

ELF Illuminates the Conflict

One target of the cell's wrath was a company called Superior Lumber. The film lets us listen to members of the "terrorist" team as they recall how they prepared for the attack, logistically and psychologically.

This is one of the most extraordinary moments of the film — a rare opportunity to hear people that the government prosecuted as "terrorists" calmly reflecting on what they did and how they justified it. And they go into great detail about how they learned to, essentially, begin living like undercover secret agents. Even today, the government remains impressed by the expertise these ELF activists developed in organizing assaults and avoiding detection. As one police officer confides, with an appreciative laugh: "The were really good at what they did!"

When the film catches up with McGowan, he is free on bail and living with family in Manhattan. With New York's memories of the 9/11 attacks, McGowan draws an important distinction about the term "terrorism." "We aren't accused of flying planes, trying to hurt people, " he says. "It's property destruction. Call it what it is."

But sometimes even property destruction proved unacceptable. In May 2001, ELF staged a twin attack on a tree farm and a university research station. It proved a disaster. The university fire raged out of control and destroyed a valuable horticultural library; it turned out that the tree farm, targeted for doing research in genetic modification, was actually using traditional breeding techniques.

McGowan began to question his justifications for property destruction. Another split developed when other members of the ELF cell proposed kicking the violence up a notch by targeting the owners of timber companies — a suggestion that McGowan found "repulsive."

The ELF cell began to collapse and McGowan decided property destruction was a dead end. Renouncing his life as an extreme monkeywrencher, McGowan returned to New York, got a job with an environmental foundation and, later, with an organization devoted to stemming domestic violence.

After more than three years of fruitless investigations, the FBI finally got a break that lead to the arrest and conviction of McGowan and 13 compatriots.

'One Man's Terrorist Is Another Man's Freedom Fighter'

Ignored in most of the media hoo-hah over the indictment of the "homegrown eco-terrorists" was the question as to whether their acts legally qualified as terrorism. As one of McGowan's lawyers points out: ""Concern for life" was fundamental to the ELF's missions. There were at least 1,200 actions linked to the ELF and the Animal Liberation Front over the years without "a single injury or death. Those statistics don't happen by accident."

There is more than one definition of "eco-terrorism." Many environmentalists argue that some of the world's greatest eco-terrorists are multinational corporations. Massive property damage — and loss of life — happens on a daily basis because of the predations of resource-exploiting corporations. Yet, despite the deaths of people killed in landslides triggered by clear-cutting, the deaths and damage from industrial explosions, and the loss of wildlife and livelihoods from oil spills, the FBI is not tapping the phones of CEOs or throwing law-breaking industry leaders into prison.

While If a Tree Falls was being filmed, McGowan was sentenced to seven years in prison and branded a "terrorist." In a poignant denouement, the camera follows him as he returns to Oregon's ancient forests for a final visit among the towering trees and free-flowing rivers.

McGowan started serving his seven-year sentence on July 2, 2007, locked inside a special "terrorist management unit" in Marion, Illinois. He will be eligible for release on June 5, 2013.

Toward the end of the film, Kirk Engdall, the Assistant US Attorney who pursued and indicted McGowan, offers a surprising assessment. "As I get older, the more circumspect I become," he tells the filmmakers. "I know now that the world is not black and white. When I first read about these arsons and got involved… they're not very likeable people at all. Once you get to know them, as a human being, you start looking at their motivations" and discover that, "instead of being just a cold mug shot or a piece of paper, they become human beings."

The film's Oscar odds may be slim, given the competition — an injured war vet adjusting to civilian life, three boys unjustly imprisoned for murder, a hangdog high school football team that becomes a winner, and a tribute to a dancer, her career, and her untimely death — but, for revealing an important true-crime story through the eyes of the participants, the film remains a winner.

If a Tree Falls beams an important message that should never be lost in the raging debate over the use of "violence from below." The lesson is this: Once you take the time to know and understand their personal experiences, in many cases these "terrorists" turn out to be fairly ordinary people whose altruism may have gone awry but whose fundamental motives merit understanding and, perhaps, sympathy.