PANAMA CITY -- Television news here aired riveting footage recently of a nation in crisis. Riot-helmeted police beat protesters senseless in the streets. Cars burned. A dictator in military uniform pummeled the air with his fists, stoking the crowd into a nationalist frenzy.

That was Panama a year ago, but the images seemed as remote as the distant echoes of another era. That Panama has disappeared.

Today, nearly 10 months after the U.S. invasion, Gen. Manuel Antonio Noriega has been replaced by a civilian president whose benignly chubby figure and high-calorie snacking habits have earned him the nickname Honeybun.

The feared and notoriously corrupt Panama Defense Force, humiliated in the invasion and revamped by the new civilian authorities with active U.S. participation, is now a police force in transition. The old cowed media that paid slavish homage to Noriega has given way to a riotously critical assortment of newspapers and talk shows.

An independent, if inefficient, legislature is in place. New judges widely praised for their integrity have ascended the bench. And Panama's service-based economy, having shriveled by nearly a third under the weight of U.S.-imposed sanctions and official corruption, is slowly regaining its former zest.

But dozens of interviews offered hints of growing impatience that the changes so far, while for the better, are not deep or urgent enough to fulfill the hopes spawned by the invasion. "Expectations were high, and satisfaction is low," said Ruben Carles, the controller general. "You can't change 21 years of dictatorship overnight. It's not easy."

A bloated bureaucracy is being reduced, but at a glacial pace. At least one Panamanian in five has no job, and the rate is much higher in urban disaster areas like the city of Colon, on the Atlantic coast. The government predicts a robust growth rate for the economy this year, perhaps 7 percent, but for tens of thousands of poor, generally darker-skinned Panamanians, the statistic is an empty promise.

President Guillermo Endara, the civilian who was sworn in as the nation's leader the same night that American troops swarmed into the capital, has removed most of Noriega's stalwarts from the upper levels of government. But in the middle ranks and in labor unions, trade associations and banks, his backers remain, many Panamanians say.

Endara has served as an amiable figure of national reconciliation, but he is often upstaged by his more forceful, politically experienced vice presidents, Guillermo Ford and Ricardo Arias Calderon.

"In essence, we have what we really want, which is weak government," said Roberto Eisenmann, publisher of the newspaper La Prensa. "After 21 years of strongman rule, we now have a president who is not a threat to anyone."

Endara is widely viewed as unsympathetic to the plight of the poor. His government, whose top officials are mostly well educated white businessmen, has done little to broaden its political base or appeal to the have-nots who supported Noriega and his autocratic predecessor, general Omar Torrijos.

Many of Noriega's team have escaped calls for justice. A half-dozen are still holed up in embassies here, where they took refuge during the invasion. Many are said to have bought or bailed their way out of overcrowded prisons.

Panama's justice system is at a virtual standstill, with about 17,000 cases pending, the vast majority of them involving common crimes. Less than 15 percent of the nation's 3,000 prison inmates have actually been tried.

Attorney General Rogelio Cruz said prosecutions of well-known officials of Noriega's government may occur in 1992. Today, said Cruz, of the hundreds of Noriega officials charged with crimes, 30 or so are in jail.

While Cruz and other officials speak of respect for due process and warn against a witchhunt, their standing in opinion polls declines.

"I know of no constitutional government that can make revolutionary change overnight," said Vice President Arias Calderon, whose main task has been to transform an army known for thuggery and thievery into a courteous, effective police force.

"Constitutional governments are made of checks and balances," he said in an interview. "If we had de facto powers, we could reshape the country. But that's not what our whole fight was about."

It is not only the political fortunes of Endara's government that are on the line. For the United States, too, the reconstruction of Panama is a test of whether the invasion and arrest of Noriega were anything more than a spectacular drug bust.

Nearly everyone concedes the difficulties of the challenge. Twenty-one years of autocratic rule have made a lasting imprint on Panama's institutions and political habits.

The United States, whose long-standing support for Torrijos and Noriega helped them build a powerful and repressive officer corps, is attempting to safeguard Washington's substantial interests in Panama through a democratic government.

In this modern capital, whose luxury apartment buildings and soaring bank towers resemble Miami more than a Central American city, the physical scars of the largest U.S. combat operation since Vietnam have been razed, replastered, repainted and rebuilt into near invisibility. Aside from 120 military policemen who continue on joint patrols with Panamanian police, American troops have gone home or returned to their bases in Panama.

Were it not for the scorched facade of the controller general's building or the weedy lots where the burned wooden tenements of El Chorillo used to stand, a visitor might even forget that the midnight blitz ever took place.

Panamanians, however, have not forgotten. Many say the invasion still enjoys broad popular support here. Nonetheless, analysts say it also deepened a psychology of dependence on the United States, while at the same time aggravating Panamanians' already prickly nationalism.

Anti-American demonstrations are staged on the 20th of every month to commemorate the Dec. 20 invasion. A group called M-20, or the 20th of December Movement, has claimed several bombings, including one that killed a U.S. soldier at a Panama City night spot.

Still, Panamanians turn reflexively to the United States to deal with nearly everything.

"Anytime anything goes wrong, somebody picks up the phone and calls us to fix it, and we've done it," said Ambassador Deane Hinton. "It's a fundamental problem," he said; "our presence exaggerates Panamanian nationalism."

So deep is the notion of connectedness that it is rare to find a Panamanian who believes that Washington will really withdraw its thousands of troops and close its military bases here at the turn of the century, despite an explicit treaty commitment signed by president Jimmy Carter.

"We just can't imagine it, therefore we can't believe it," said a lawyer. But American influence is undiminished for now, and a primary concern is the reconstruction of Noriega's army.

Renamed the Panamanian Public Force, the Panamanian troops who used to beat protesters in the streets have been issued pistols to replace their AK-47s and put through seminars sponsored by the U.S. Justice Department.

Three successive military colonels, remnants of the old defense force, have been dumped from the new force's top job. Last month, 142 of the highest-ranking officers were "retired," along with the commander, Col. Eduardo Herrera Hassan, who had balked at demilitarizing the 12,000-member force.

Although many Panamanians remain scornful of the new force, its transformation is being handled with consummate political skill by Arias Calderon, diplomats say.

The ousted officers, who might have put up a fight had they been handled roughly, were offered full retirement benefits. And the removal of more than half of all the colonels, lieutenant colonels, majors and captains has opened career opportunities for junior officers.

Last month, the government named a civilian as the new police chief -- Ebrahim Azvat, a Harvard-educated PhD and lawyer. "By putting in a civilian chief of police, there's a message to all concerned that it was time to climb on board, and if you're not going to be part of the transition, you're gone," said a U.S. official who advises the police force.

Diplomats and Panamanian officials say more "retirements" are expected. But many Panamanians say they want to see more dramatic change before they are persuaded the country is on the right course.