Australia passed some of the toughest gun-control laws on Earth last year, and it's easy to understand why: A man with a gun broke this big, tough country's heart.

On a warm Sunday afternoon in April 1996, a gunman killed 35 people and wounded 19 more with an array of assault rifles here on the southern shores of the island of Tasmania, in one of Australia's most popular and crowded tourist destinations.

As he drove away from the crowded cafe where the shooting began, he found Nanette Mikac and her two young daughters running away. Mikac flagged down his car, thinking it was a ride to safety. The gunman stopped and ordered Mikac to her knees, and as she pleaded with him, "Please don't hurt my babies," he fired one shot through her forehead and several shots into 3-year-old Madeline.

Alannah, 6, ran into the woods when she saw her mother and sister die. The killer hunted her for nearly two minutes. When he found her curled up behind a tree, he put the hot muzzle of his AR-15 assault rifle to the back of her neck and nearly blew her head off.

"We are all different people now," said Keith Moulton, 67, visiting the spot where his daughter and grandchildren died. "This has changed the whole of Australia."

Within two weeks of the killings, the government introduced legislation banning possession, manufacture and sale of all automatic and semiautomatic weapons and pump-action shotguns. It introduced an extensive gun registration system; a 28-day waiting period between obtaining a gun permit and buying a weapon; a provision that all first-time permit applicants receive firearm training; and new requirements that weapons and ammunition be stored separately.

In a country with a long tradition of shooting and gun ownership, the new laws were a startling cultural change. A grief-stricken Australia did overnight what gun-control advocates in the United States have been unable to accomplish in decades.

Although the United States bans some automatic and semiautomatic guns, Australia's new ban is far more comprehensive. Handguns effectively have been banned here for decades, and there is little handgun violence in Australia.

Still, Australia has a vast number of guns. Estimates range from the government's guess of 2.5 million to the gun lobby's claim of 10 million -- more than one gun for every two Australians. In Australia's vast and sparsely populated Outback, people say they don't know anyone who does not own a gun. But in its coastal cities, particularly Sydney and Brisbane, people say they don't know anyone who does.

The Port Arthur killings brought together many people on both sides of the gun debate. In a land of only 18 million people, nearly everyone knew someone, or knew someone who knew someone, who was among the 500 or so people in the small waterfront historic site at Port Arthur that day. Australians took the murders personally: Polls showed 95 percent favored the new laws. Australians also were willing to reach into their own wallets to get rid of guns. The government established the world's most comprehensive gun buyback program, offering to pay anyone fair market value for any of the newly banned guns. When it ended Sept. 30, more than 640,000 guns had been turned in by owners who collected the equivalent of more than $267 million. The government has set aside nearly $95 million more to compensate gun-shop owners for lost business. When the total is tallied, the program is expected to cost every Australian taxpayer about $57. Many people seemed eager to ditch their guns. Moulton said a neighbor came home from a memorial service for his daughter and granddaughters, placed his .22-caliber hunting rifle in a vise and smashed it over and over with a hammer. "To him, that gun represented the loss of people he knew," Moulton said. "There was such an uprising that there is a real stigma to guns now. Anybody who brings one of those guns out into the fresh air is marked." There was, of course, opposition to the new gun restrictions: Gun owners argued that the laws would not reduce gun crime and would unfairly penalize law-abiding sport-shooters. They said criminals would be emboldened because more of their victims would be unarmed. And they staged large rallies. Gun owners here always have been a powerful lobby, but they were surprisingly ineffective this time, despite support from the U.S. National Rifle Association. Mainstream gun owners often found their credibility undercut by extremists. Ian McNiven, an official of the Firearm Owners Association of Australia, argued that Australian civilians need their guns to protect their nation from invasion by other Asian nations, particularly Indonesia. Others sent death threats and fake letter bombs to legislators working for gun control. Prime Minister John Howard wore a bulletproof vest to a rally supporting the new laws. It is still too soon to tell whether the new gun laws will cause a long-term reduction in crime. Australia already has relatively low violent crime rates. One recent study shows that gun crime actually increased 13 percent during the year-long gun buyback program. But gun-control advocates say the statistics don't explain what is happening in Australia. "It was symbolic," said Phillip Adams, a prominent columnist and radio talk show host, who turned in several of his guns. "The whole country feels better." The gunman, Martin Bryant, who is serving life in prison -- Australia has no death penalty -- has never publicly said why he started killing. But he once alluded to Port Arthur's violent past as a British penal colony, telling authorities, "It must be the most violent place in Australia. It seemed the right place."

Walter Mikac, a pharmacist shattered by the loss of his wife and daughters, became a strong voice in the gun control debate. But, like many Tasmanians, he has since moved from the island state to mainland Australia.

Interviewed in his small waterfront home 19 months after the killings, Moulton still occasionally welled up when he talked about "my girls." His house is filled with photos of them: the two girls clowning for the camera with sunglasses on and front teeth missing; a family portrait in Port Arthur; a picture of them with Moulton's wife, who died of lung disease three months before the killings.

As Moulton showed a visitor where his daughter was killed, he crouched over the spike police had hammered into the asphalt to mark where her head came to rest. He retraced the path where Alannah ran, stopping at what is now known here as "Alannah's tree," where a stranger had laid a fresh bouquet of purple irises.

Then he walked away and waved goodbye, knowing he would be back here many times. CAPTION: Keith Moulton points to names of his daughter and granddaughters on memorial to massacre victims. At left, Alannah Mikac, 6, and sister Madeline, 3, clown for camera shortly before they were killed. CAPTION: Martin Bryant was sentenced to life in prison for the April 1996 killings.