In the 19th century range wars, ranchers cut fences, burned buildings, shot livestock and each another. As the millennium nears, a new range war has broken loose with cattlemen on the defensive against an unseen enemy - the radical fringe of the environmental movement.

In this war, environmental terrorists strike isolated ranches on the western range with the goal of driving ranching from public grazing land. The terrorists eschew showdowns at high noon in favor of sneak attacks. Their weapons? Fence cutters, assault rifles and the torch.

They have left a widening trail of damage across 10 western states where public range is essential to ranching. Cattle have been shot, water tanks destroyed, corrals and buildings burned, and fences cut.

But the war on ranching is only part of the picture. The radical fringe has targeted virtually the entire economic underpinnings of the rural West - oil and gas, logging, hydroelectric power, mining and tourism.

In Utah, radicals bombed a fur cooperative. In Oregon, they burned a hydroelectricplant. In Washington, they sabotaged logging equipment. In Montana, they disrupted the Montana Mining Congress with a bomb threat. And in Colorado, a group called the Earth Liberation Front claimed credit for arson that caused more than $12 million in damage to a Vail ski lodge.

The October fires in Vail may be the costliest example yet of environmental terrorism. But some observers predict worse to come. "The magnitude of it is only going to get bigger," predicts Barry Clausen, a California-based expert on the radical environmental movement.

Ironically, the breadth of the terrorism movement may play to the advantage of ranchers. If ranchers had to battle terrorism alone, they might lack the clout needed to get action from law enforcement, Congress and western legislatures. But the ranchers have allies in every major western industry. Ranching, mining, oil, logging and tourism together carry considerable political and economic clout.

The war on the West only recently has gotten much public attention. Typically, ranchers have been reluctant to publicize sabotage. "They're not reporting it for fear the publicity will encourage it," says Julie Bousman, spokeswoman for the National Cattlemen's Beef Association.

But as the range war escalated, ranchers have begun reporting terrorism to authorities and the media. The ranchers have little choice. What began as harassment has turned into a campaign that could drive them out of business.

Deadly Acts Of particular concern is the growing wave of cattle killings. "If somebody shoots five head, you're looking at a $2,500 loss," says Betsy Macfarlan, executive director of the Nevada Cattlemen's Association.

"That could easily be the grocery and fuel bill for the next four or five months. If there's a mother cow and she's got a wet calf that's not old enough to be weaned, that's two animals you've lost."

Some ranchers have suffered far bigger losses. In Deming, NM, for example, 22 head were shot on one rancher's public grazing allotment. A water tank and windmill were damaged in the same attack.

While the ranchers have often been reluctant to publicize the war on the West, environmental radicals have not. One Internet posting urged readers to "Hunt Cows, Not Cougars," reports Clausen. And the fringe Earth First! group recently carried an article in its magazine entitled "Fence Mending 101." The article describes fence cutting techniques.

In this new range war, fence cutting is the most prevalent tactic. It can be done quickly and silently with little chance of detection. For example, extremists cut more than 200 fences in central Wyoming in the spring of 1997 - 60 of them at one ranch, the Clear Creek Cattle Co.

A group called Islamic Jihad Eco-Terrorists Inc. claimed responsibility. Signs left at fence-cutting scenes read: "Just in time for the Welfare Cowboys Convention," a reference to the annual Wyoming Stockgrowers' Convention that took place as the fencing was being cut.

Fortunately, fence cutting is often just a nuisance, especially if discovered quickly. At Clear Creek, the fence cuts were discovered early and only 20 or so cows had mixed with a neighbor's herd.

But fence cutting can lead to bigger problems if not discovered early. "If it would have been four or five days before the cuts were found, we could have had hundreds of our cows mixed with hundreds of the neighbor's cows," says Rob Hendry, co-owner of the ranch. "It would have taken at least a week to separate them."

And if fence cutting occurs along highways, it could lead to disaster if freed cattle wander into lanes of fast-moving vehicles. In that case, ranchers could face lawsuits filed by victims of car-cattle collisions.

Killing Cattle But it is the outright slaughter of cattle that holds the biggest threat. "Fence cutting is a nuisance crime," says Rob's wife, Leslie. "We can replace fencing. We can replace water tanks when they shoot holes in them.

"When they start shooting cattle, that's when it's really going to get dangerous. Once they start doing that, you know they're armed. So when you come across them, you don't want to confront them. They might shoot you.

"Econo mically, you can't survive if they start killing your money machine," she says. "We keep cows an average of 10 years. If they kill a mother cow you lose nine calves. Then you have to replace them."

The wave of sabotage has spurred state cattlemen's groups to offer rewards. But catching terrorists is difficult. In the vast unpopulated western range, there are almost never any witnesses. Cut fences and burned line shacks may not be discovered until terrorists have long since vanished.

"We've got ranches that run for hundreds of miles," says the Nevada Cattlemen's Macfarlan. "The rancher may not come back to a section for six months or longer. By then, the trail is pretty cold.

"Unfortunately, some of these causes are starting to get violent," she says. "They decide they can't get the message across through traditional methods, so they decide to destroy other people's livelihoods as a way of getting their message across. They don't care what damage they do. It's all for the cause."

Cut Off The Money Environmental terrorism runs on the same fuel as international terrorism - money. To stem the tide of eco-terrorism, ranchers and other targets must stem the flow of cash, says Clausen.

To do that, Clausen says victims must publicize acts of environmental terrorism. In the past, some victims have been reluctant to report fence cutting and other terrorist acts because they believed publicity would encourage more terrorism.

But Clausen argues that big-ticket donors who fund radical groups will be more likely to shut their checkbooks if instances of violence and sabotage are widely publicized. "People don't want to be connected to these things," he says. "They want to maintain a certain amount of respectability."

Publicity also encourages Congress and state legislatures to pass tougher anti-terrorism legislation. "Many Congressmen and Senators don't think it's a big issue," he says. "The reason they don't think it's a big issue is because nobody is reporting it. When it's reported and publicized, Congress will pass tougher laws."

Stemming the cash flow is particularly critical because terrorists can't operate without it. The money allows them to devote their time to sabotage instead of work.

Money also pays for travel, lodging, phone bills, computer costs, maintaining Internet sites and other expenses associated with terrorist operations.

Barry Clausen, an expert on environmental extremists, offers these tips for dealing with eco-terrorism:

* Take care not to damage evidence at sabotage scenes. Shell casings and spent bullets are evidence. So are tire tracks, footprints, burned out buildings and corrals, notes left by the criminals, samples of cut wire and even discarded trash.

For instance, when Wyoming authorities investigated fence cutting at Rob Hendry's Clear Creek Ranch, they made plaster casts of tire tracks and footprints in the area. "They handled it just like a crime scene, which it was," says Hendry.

* Equip every ranch vehicle with a pen and notebook to take down license numbers of suspicious vehicles. "If you see any vehicle that looks suspicious, write the license plate number down first, then if there's time get a description of the vehicle and its occupants," says Clausen.

The plate number can identify vehicle ownership, or in the case of rental cars, the name of the person who rented it. License plate numbers can be cross-referenced against computer databases of vehicles operated by known radical environmentalists. Clausen's firm, North American Research, maintains one such data base. North American can be reached by phone at 707/442-0115. Some law enforcement agencies may also keep such data bases.

* Do not confront suspected terrorists. People who shoot cattle are armed and should be considered dangerous. "If you get some wacko on the verge of getting caught, somebody could die," Clausen says. Instead, call authorities immediately.

Radical environmental groups believe wildlife would fare better if ranchers and their cattle were gone from public lands. But would it?

This may be a prime example of the adage "beware of what you ask for because you may get it." In this case, if the ranchers go, so may much of the wildlife.

If ranchers lose the use of public lands, many would go out of business. Private landholdings often are too small to profitably run cattle in the arid West where grass is sparse.

To make ends meet, failed ranchers would probably liquidate their private landholdings. Here's where wildlife gets hurt. Public lands are often the most barren stretches of the West. Streams and rivers usually flow through private landholdings. And if the rancher sells, much of the land will be carved into subdivisions and "ranchettes" - fenced tracts of 20 acres or so. Once that happens, wildlife is blocked from the water supplies needed for survival.

Many environmentalists realize this and they are campaigning to keep ranchers on public lands. But others are mounting an ever more violent campaign to rid the public range of cattle. If they get their wish, they may quickly find that the adage "beware of what you ask for" is as true today as the day it was coined.