The sun had just broken through a heavy overcast when an elderly man, his head bowed, stepped from the shadows of Parliament House to take oath as Uganda's new president.

Yusufu K. Lule's fingers fidgeted at his side that afternoon last April. His eyes swept the crowd gathered in Parliament Square as he spoke. The nightmare, he said, was over. With the overthrow of Idi Amin, a new era of national reconciliation had begun.

Church bells greeted his words. In the square, thousands of Ugandans cheered and stomped and wept with joy, hoisting the victorious Tanzanian soldiers to their shoulder and joining in the new national anthem. It was a giddy, joyous moment and, for the first time in eight years, Ugandans had hopes and prayers for the future.

Today, just four months later, it is clear that there will be no miracles in Uganda. The euphoria has given way to skepticism. The dreams of national unity have been subverted by personal ambition and greed. Uganda is a dispirited country teetering on the brink of new disasters.

The Tanzanian army of liberation has become an army of occupation. Near anarchy reigns in parts of the countryside, and Kampala is ruled at night by roaming bands of uniformed murderers. The economy remains a shambles, with most shops still shuttered. The government is beset by tribal and ideological differences and maneuverings for individual power.

"There was so much jubiliation back in April, such a wonderful feeling of national cooperation," said Anglican Archbishop Silvanus Wani. "It's hard to understand how it soured so quickly, but for now people are living in fear and suspicion, and worry about what is going to come next."

Lule, 67, was ousted after only 68 days by leftists on the ruling National Consultative Council.

He was replaced by Godfrey Binaisa, 60, a lawyer widely disliked in Kampala. Lule was taken from Uganda and held under house arrest for two weeks in Tanzania.

Binaisa has announced that there will be free elections in Uganda by June 3, 1981. But two years is a long time in a country as troubled as Uganda.

The National Consultative Council, the most ideologically diverse governing body in Africa, includes Marxists, monarchists and capitalists. All 30 members lived in exile during all or part of Amin's reign, a cause of deep resentment among the 12 million Ugandans who stayed behind and believe they have been denied representation.

If we'd all run away, who would have looked after the country," a doctor said. "So these new boys can't come back after living abroad and eating well for eight years and say they are going to rehabilitate me. I hope they realize that those of us who stayed here are tough. You had to be tough to survive under Amin."

Binaisa says the council will soon be expanded to about 100 people for greater representation.

Hundreds and probably thousands of Ugandan civilians have been killed for nonpolitical motives -- usually robbery or the settlement of old scores -- since Amin was overthrown. Living in Uganda is so precarious these days that people are murdered for their watches or radios, and no one dares drive a luxury car, night or day, in this lawless capital.

The impoverished Tanzanian soldiers who marched into Kampala last April with only their guns and uniforms are now well stocked with gold bracelets, watches, transistor radios and Mercedes-Benz automobiles. They have not been paid since they left Tanzania and simply live by taking what they want at gunpoint.

Last month the government ordered the approximately 25,000 Tanzanian soldiers still in Uganda back to the barracks and prohibited them from carrying weapons except while on duty. The Ugandan guerrllias who helped the Tanzanians capture Kampala were shipped out of the capital.

The move improved the situation, but murders in Kampala continue, often with a dozen or more people killed daily by robbers.

An eerie silence, broken only by the sound of gunfire, descends at night on the capital of 500,000 residents, living behind bolted doors. The killers wear military uniforms but no one is sure whether they are Tanzanians or Ugandans. To the terrified population, they are simply "the unknown people."

Western diplomats have stocked their residences with shotguns, gas grenades, and, in some cases, bodyguards flown in from their home countries.

A Swiss diplomat recently fought off a gang of uniformed attackers, firing at them from his bedroom window with a sawed-off shotgun. The weapon's recoil knocked out three of his front teeth, but the thugs fled emptyhanded.

Many of the crimes undoubtedly are being committed by the 4,000 convicts the government released from prisons when Kampala fell because no food was available to feed them. The government has ordered their arrest by the police force, which disintegrated in the final days of the Amin regime. Until the force can be reconstituted, the council cannot enforce its edicts.

Also threatening Uganda's long-term security are private armies. The Marxist defense minister, Yoneri Museveni, has a 10,000 to 15,000 member tribal army -- recruited in the south while the war was under way in the north. The minister of power and communications controls 7,000 guerrillas from the Save Uganda Movement. Chief of Staff David Ojok, a backer of former president Milton Obote, has perhaps 8,000 men from the Uganda Liberation Army under his command.

It is unclear whether these forces will be asborbed by the national Army now being formed. They are controlled by radical elements on the council, and this gives the left considerable leverage against Binaisa and the ministers involved with economics and agriculture, all of whom are so-called moderates with Western ties.

"I suppose our expectations were unrealistically high when Idi Amin was overthrown," said a Catholic nun, Sister Neevis Kizito. "Everyone thought that after all we'd been through with Amin, the country and the government would finally be willing to pull together.

"Now, sometimes I wonder if we aren't creating the same conditions that gave birth to a person like Amin in the first place."