CAMBODIA'S SECOND PRIME Minister Hun Sen knew how to stage a coup. The longtime communist assembled a loyal private army and sent it into action in the predawn darkness of July 5. It struck throughout Phnom Penh with tanks, rockets and mortars, routing the forces of the first prime minister, Prince Norodom Ranariddh. Three days later, 60 civilians and troops on both sides lay dead as Cambodians and foreigners rushed to flee the capital. Hun Sen's men fanned out into the countryside, rounding up confederates of Ranariddh, shooting some dead and announcing their "suicides," pressing others to swear allegiance to Southeast Asia's newest unchallenged strongman. Warned at the last minute of the impending coup, the prince had fled to Paris. The new boss swaggered into a press conference, almost giddy with victory. He advised photographers not to miss the historic moment. "I am captain alone," Hun Sen declared.

So one of the world's most hopeful experiments in democracy comes to a crashing close. Only four years ago the United Nations sponsored Cambodia's first free elections, hoping to end a long civil war and nearly a decade of communist rule under Hun Sen. Ranariddh's clean victory in that election was widely hailed as a model for other troubled nations, but Hun Sen refused to accept defeat. He threatened to take up arms. U.N. negotiators had little choice but to cede the rough former rebel a share of the prime minister's post and hope he would be content with that. He never was. As opposition leaders fled in fear for their lives last week, a maniacally confident Hun Sen said he had acted to halt the "anarchy" of Ranariddh's rule. He compared Ranariddh, who had gone to the United Nations to appeal for the world's help, to Mike Tyson biting in the face of defeat: the last resort of a loser. Ordinary Cambodians, however, were in no mood to gloat. Again and again on the streets of Phnom Penh, they said Hun Sen had brought back the "nightmare" of communist-style rule.

Hun Sen has done far more than topple the freely elected leader of Cambodia. He has undermined the revival of a country still struggling to overcome the genocidal reign of the radical Khmer Rouge in the late 1970s, and the communist regime that followed. As a few intrepid tourists, traders and investors returned to Cambodia in recent years, its neighbors had welcomed the prospect of a peaceful capitalist democracy next door. Now the beacon light is out: "We have failed, completely failed," said Ranariddh at the United Nations. The Association of Southeast Asian Nations (ASEAN) was prepared to admit Cambodia along with Burma and Laos later this month, but suspended Cambodia's invitation after the coup. In an exclusive article for NEWSWEEK, acting Malaysian prime minister Anwar Ibrahim says Southeast Asia must rethink its traditional passivity, and consider active intervention to prevent crises like the one unfolding in Cambodia (following story). The United States, Japan and Germany temporarily halted aid programs to Cambodia, which relies on foreign largesse for more than half of its $600 million national budget. To one Cambodian journalist, it seemed that "all the energy and effort we put into getting the country back on its feet has been destroyed in just 48 hours."

Asia's new strongman came as a surprise, but only because high hopes for Cambodia obscured what everyone knew about Hun Sen. He was a battle-hardened communist before he was an adult. Caught up in the spreading Indochina war as a teenager, he joined the Khmer Rouge side and lost his left eye to the fighting. But Hun Sen would garner no rewards after the rebel victory in 1975, only the paranoid suspicion of Khmer Rouge mastermind Pol Pot. Facing a purge, Hun Sen fled with his unit to Vietnam. When Vietnam toppled Pol Pot in 1979, it installed Hun Sen as one of its puppet rulers in Phnom Penh. The Khmer Rouge continued to fight Hun Sen, often in alliance with the forces of Prince Ranariddh's royalist party, Funcinpec. Then came the 1993 elections. Fighting subsided. The Khmer Rouge began to break up. What Cambodians now fear most is a revival of the civil war. Already, diplomats say, Funcinpec militants are reaching out to the Khmer Rouge, seeking to revive their old alliance against Hun Sen.

He will be ready. During the 1993 campaign his Cambodian People's Party dropped the communist label, but never truly relinquished power. The CPP retained most posts below the ministerial level. Hun Sen was too tough for the refined prince, forcing him to drop two key allies (including his own uncle) from the cabinet. Hun Sen also retained operational control of the armed forces, making it easy for him to build up his own private army. He is obsessed by fears of assassination and has been beefing up the force of 1,500 bodyguards who surround his heavily fortified residence, the "Tiger's Den," outside Phnom Penh. As relations decayed between the ill-educated farm boy and the prince, both men began recruiting former Khmer Rouge to their personal security forces - even though the Khmer Rouge is officially banned in Cambodia.

According to a foreign diplomat with contacts inside the CPP, Hun Sen decided to topple Ranariddh with an old communist ruse. He would "create an incident so the CPP could react militarily and wipe Funcinpec out." First Hun Sen denounced Ranariddh as a "criminal" for recruiting the Khmer Rouge and receiving arms shipments, even though he was doing the same things. Then he manipulated a government committee set up to end fighting between the CPP and Funcinpec. Hun Sen's men began pressuring the committee to search Funcinpec military camps for Khmer Rouge fighters and arms. The houses of Funcinpec party officials were raided. The provocation worked. Earlier this month a firefight broke out at a naval base north of Phnom Penh as CPP men searched for "illegal" Funcinpec troops. The next day, July 4, CPP military police disarmed a group of 70 Ranariddh bodyguards.

The prince's security men warned that a coup was in the works and urged him to flee. Ranariddh immediately hopped a plane for Paris, hours before the real battle. Just after dawn, Hun Sen's tank troops overran the Funcinpec base at Ang Snoul, 10 kilometers from Phnom Penh's international airport. That afternoon, as CPP Defense Minister Tea Banh assured a meeting of foreign diplomats that all was calm, loud explosions could be heard. It was Hun Sen's forces firing mortars, rockets and small arms at the residences of tour senior Ranariddh advisers, including the home base of army deputy chief of staff Nhiek Bunchhay. Ostensibly, this was another attack on "hidden" Khmer Rouge soldiers, but it was led by a commander who is a Khmer Rouge defector himself.

By then Hun Sen had already launched a purge, borrowing from Pol Pot's lessons on how to consolidate power. He issued a list of Ranariddh loyalists who should be arrested for plotting against him. He said Ranariddh was free to come back "to face court" proceedings—an offer the prince was hardly likely to accept. Not after Hun Sen's men stormed his Phnom Penh residence, where guards raised a white flag of surrender. The attackers looted the house (taking several Mercedes cars) and moved on to other targets on Hun Sen's list. Ministry of the Interior official Ho Sok was taken to his own ministry and killed by at least two AK-47 rounds to the head. His death was later reported as a suicide in a CPP-affiliated newspaper, which also claimed Funcinpec intelligence official Chao Sambath had killed himself by biting off his own tongue. CPP sources privately admit Chao Sambath was executed along with three generals and as many as 60 soldiers. Hun Sen admitted no such thing. "This is not a coup," be insisted. "No politician has been arrested, political parties remain untouched."

SO FAR AS IS KNOWN, THE hundreds of captured Funcinpec soldiers are being held under armed guard in pagodas and makeshift detention centers. CPP sources say they will be transferred to a prison camp near Phnom Penh under the control of a provincial governor with a history of violent behavior. Many of the prisoners, according to CPP sources, will be held for "psychological and political re-education," an eerie echo of communist rule. Outside Phnom Penh, some Cambodian sources say, Hun Sen forces are systematically arresting local Funcinpec officials and have detained 125 so far. One Cambodian who works for a foreign company says the "climate of fear and depression reminds me of the way Phnom Penh was in 1975, as the Khmer Rouge began ordering everyone out of the city and into the countryside."

Hun Sen has tried every trick in the communist book of subversion. Using money and political intimidation, he orchestrated a split within Funcinpec earlier this year. He swayed provincial Gov. Toan Chay and several National Assembly deputies to form a rival Funcinpec party. Now Hun Sen is expected to persuade some Funcinpec leader to betray Ranariddh by taking his post as first prime minister. That would help support Hun Sen's claim that nothing of substance has changed. He says Cambodia still has the same Constitution, the same political parties contesting National Assembly elections scheduled for next year, even the same head of state: Ranariddh's father, King Norodom Sihanouk. The difference is that now all serious challengers to Hun Sen are exiled or dead. "I fear the human-rights movement may be finished here unless the present trend is reversed." said one activist.

Hun Sen is already campaigning for status more grand than second prime minister. He travels frequently to the countryside, where his advance team makes sure the crowds and the LONG LIVE HUN SEN banners are in place before he arrives. During a recent trip near the Vietnamese border, he inaugurated yet another "Hun Sen" pagoda.

"Hun Sen" dormitory for monks and "Hun Sen" school for monks. He prostrated himself before saffron-robed monks, and handed out thick envelopes stuffed with cash to locals. Hun Sen may campaign like a Marxist autocrat, but he has a pragmatic streak. He was instrumental, for example, in loosening the regime's controls on Buddhism. "I've been called a communist, a pro-Vietnamese, an ex-Khmer Rouge," he recently told NEWSWEEK. "Finally I have to define myself to the world: I am Hun Sen, a pro-Cambodia Cambodian."

Nationalism is no longer enough to ensure his welcome in Southeast Asia. The coup solidified Hun Sen's reputation for unpredictable outbursts of irrationality and violence. He can be smart, even subtle, but "too often Hun Sen's way of solving problems is by force," says one Asian diplomat. His troops are suspected, to cite just one example, of plotting a 1995 grenade attack that left two dead at a congress of the pro-Ranariddh Buddhist Liberal Democratic Party. The day before, Hun Sen publicly warned the party leaders to cancel the congress—or risk a grenade attack. "You don't want to corner a man like Hun Sen," says one Western observer in Phnom Penh. "You don't want to put him in a position in which he has nothing to lose."

Hun Sen warned the world to stay out of Cambodia's internal affairs as the coup progressed. But no nation with citizens or business interests in Phnom Penh could ignore the looting and vandalism. Soldiers from both sides rumbled down streets in tanks stacked high with motorbikes, TVs, even mattresses. They took gas pumps from service stations, 4X4s from a Toyota and an Isuzu dealership. They stole buses and the entire duty-free store from the airport. Then they raked the tower and tarmac with heavy weapons, closing Phnom Penh's connection to the outside world. It was three days before panicked tourists and foreign residents could begin flying out.

IT WILL TAKE LONGER FOR Cambodia's reputation to recover. The economy was growing at 6 percent annually, and the garment industry in particular was expanding with the help of outside investors. Now locals and foreigners alike are shuttering businesses and putting plans on hold. A huge Malaysian-owned floating casino on the Mekong River has been closed and all its Filipino workers evacuated. "The economy will definitely take a hard hit," says one Asian diplomat. "People are frightened." Funcinpec National Assembly deputy Ahmad Yahya took a flight out. "If I stay I'll be like a prisoner," he said. "They'll force me to say white is black and black is white."

Hun Sen's neighbors still find it difficult to call his coup a coup. The United States avoided the word in part due to intelligence reports that Ranariddh, too, was plotting a power grab, and out of recognition that both sides were cozying up to the Khmer Rouge. "There are no heroes in Cambodia," says a senior Clinton administration official. "Nobody's black or white; they're all shades of gray." ASEAN likes to think of itself as broad enough to cover all shades of "Asian values," but couldn't accept what it called the "unfortunate circumstances which resulted from the use of force." ASEAN's deliberations have already been complicated by admitting the communists of Vietnam. It is about to admit the repressive generals who rule Burma. Cambodia was supposed to be easy, in comparison. "This is a major setback," says Philippine strategic analyst Carol Hernandez. "ASEAN had put a great stake in the peace and reconciliation process, and now it's all falling apart."

Hun Sen still insists nothing has changed, other than the departure of the "traitor" Ranariddh. He does not seem to hear the anger of officials at the United Nations, who uncharacteristically denounced the "coup d'état," exasperated that the $2 billion invested in the '93 election process had suddenly been tossed away. Afterward, Hun Sen sent a note to startled Western and Asian embassies asking for yet more aid—this time to repair damage from the coup. ASEAN foreign ministers plan to recruit King Sihanouk, who has played the role of national conciliator before. But Hun Sen has already rejected the offer. "It is too late," he said. "Everything is over."

Not quite. Outsiders may be exhausted by Cambodia, and Phnom Penh is quiet, but fighting continues in the countryside. Top Funcinpec generals have escaped Hun Sen's dragnet in the capital and are seeking to reunite with their troops in the northwest. Diplomats say a Funcinpec regional commander in the Siem Reap area, Gen. Kan Savoen, has joined forces with hated Khmer Rouge leader Ta Mok, the man said to have captured Pol Pot last month. One Cambodian analyst says this force could launch attacks near Phnom Penh as soon as late August. Hun Sen, huddled in the Tiger's Den, has often predicted that if he ever becomes sole leader of Cambodia, he will be assassinated. Now, he commands alone, and Cambodia faces the prospect of a violent turn in its troubles.