AMONG the decaying buildings on Havana's Malecon seaside boulevard, a colorful billboard leaps out at a passer-by. It depicts a growling Uncle Sam straddling Florida, menacing a Cuban soldier, who looks relaxed in the shade of a palm tree in Cuba.
The accompanying slogan translates: ``Mister imperialists, we have absolutely no fear of you!''
The sign is just one of many propaganda slogans found all over the island exhorting Cubans to persevere in the face of hardships. The whipping post for all of Cuba's problems is always the United States and its 33-year-old trade embargo.
But these days - with the Cuban economy ripe for implosion - the anti-Yankee rhetoric suggests to many here that President Fidel Castro Ruz's government is more out of touch than tapped into the mood pulsing through the capital's garbage-strewn streets.
``Fidel was popular back in 1959 and 1960. I agree. But as far as I'm concerned, he's become worse than Batista, or Machado,'' rants Angel, a pensioner, as he emerges from a sparsely stocked state food store in Havana's old quarter. He is referring to two pre-Castro Cuban strongmen.
In Havana, a significant number of people such as Angel are seething. Communist economic mismanagement is responsible for reducing Havana to ruins, they say.
``No one believes in revolutionary slogans anymore,'' claims a 17-year-old student who calls himself Jose Aponte. ``People are hungry. They have no hope.''
Indeed, instead of concentrating on expressing fearlessness of the US, Cuban leaders might feel concerned that a critical mass of people is losing its fear of rising up against the 35-year Communist dictatorship.
The first sign that discontent may be reaching a boiling point came Aug. 5, when rioters - chanting ``Liberty! Democracy! Enough!'' - rampaged through old Havana. For the government, the most ominous development in the riot may have been that rioters looted several well-stocked shops that sell goods only for US dollars.
Mr. Castro - despite his antipathy for US administrations from Eisenhower to Clinton - permitted the US dollar to circulate on the island in July 1993. The move was justified as a necessary evil to salvage the crash-diving economy and, in Marxist parlance, defend the gains of the revolution.
But it may turn out the very step intended to resuscitate Cuban society could rip it apart. ``Dollarization'' already has created a wide gap among Cubans, stirring tension.
``Allowing the dollar was a bad decision,'' says Manuel, a university graduate and foreign language specialist, who in order to survive now cruises Havana's old quarter looking to latch on to tourists and serve as a ``guide'' in return for a few dollars.
``We were brought up to believe that everyone would enjoy equal rights and equal access,'' he says. ``But with dollars, this isn't the case.''
It takes only a quick glance around old Havana to understand what Manuel is talking about. While virtually all the city's residents live in comparative poverty, some are more impoverished than others.
Havana residents have to cope with indiscriminate, persistent blackouts lasting up to 10 hours a day, as the government conserves resources. There is also a water shortage. Many neighborhoods depend on occasional truck deliveries for potable water.
Most state shops that accept Cuban pesos are devoid of purchasable goods. Bookstores are a notable exception. A bevy of socialist reading materials remain on sale, including the 55-volume collected works of Vladimir Lenin, available at a bargain price.
Looking at the crumbling architecture, one might think that a battle for Havana had just been fought. Many buildings have collapsed, giving downtown a bombed-out look.
Trying to remain as inconspicuous as possible amid this searing, stinking, and unrelenting ``peso world,'' is the air-conditioned dollar paradise, offering a refuge to those who possess the US currency.
The dollar world comprises hotels, along with some restaurants and food stores. The air-conditioning in these places is usually turned up so high that, for example, some people put on sweaters in restaurants, mocking the 90-degree heat outside.
Since the dollar's legalization, the government has followed up with more reforms. First came the implementation of agricultural changes offering limited incentives to boost production. Later, there was a reshuffle of provincial party organizations. And on Aug. 4, the National Assembly approved an income tax in an effort to close a yawning budget deficit.
Castro also is determined to forge new foreign-trade ties, especially with Latin American countries. The collapse of trade with the former Soviet bloc is the principal cause of Cuba's economic dysfunction. Cuban exports dropped from $8.1 billion in 1989 - mostly with the Soviet bloc - to $1.7 billion last year, officials say.
Despite the moves, prospects for a quick improvement in the plight of the people are dim. For example, this year's sugar-cane harvest is poor, according to government estimates.
In Havana, fuel shortages have closed factories, leaving thousands of laid-off young men to languish away the days. Meanwhile, children in the old quarter pass the time begging tourists for coins and candy.
Castro has declared this year to be the ``year of youth.'' But many of Havana's young people seem far from dedicated to helping the Communists' retain power. ``When people have nothing, they also have nothing to lose,'' says Mr. Aponte, the student.
The Aug. 5 riot was perhaps only the first manifestation of such popular frustration. Castro, in a sign that he may feel vulnerable, has threatened to unleash a mass exodus of Cubans - a repeat of the 1980s Mariel boatlift that brought about 125,000 Cubans to US shores and created a logistical nightmare for American authorities.
Despite the problems, Castro retains immense personal popularity among the majority of Cubans.
``I'll believe in Fidel until the day I die,'' says Hector Viltre, a Havana cigarmaker for 48 years. ``Because of the revolution, my children had possibilities that I never had.''
In addition, the mood in the countryside is not nearly as desperate as it is in Havana. Both in Matanzas Province to the east of the capital and in Pinar del Rio Province to the west, residents say that while life is difficult, at least there is enough food.
``Havana may have nothing. But peasants have a few chickens and some rice and beans,'' says Rosario, a resident of Pinar del Rio. ``That's all they need to be more or less content.''