While there are plenty of bloggers who dish out harsh opinions on Mr. Castro, most do so from the cozy confines of Miami. Ms. Sánchez is one of the few who do so from Havana.

"What makes her so special is that she is fresh, observant and on-the-scene," says Philip Peters, a former Latin America official at the State Department who now studies Cuba at the Lexington Institute, a Washington, D.C.-based think tank. "Almost all of the Cuba blogs are written by people who travel there occasionally, or by people who haven't seen the island in 40 years, if ever," he says.

Not only does she write from Cuba, she even signs her name and posts a photo of herself on her Web site. Most Havana bloggers are anonymous. "Once you experience the flavor of saying what you think, of publishing it and signing it with your name, well, there's no turning back," she says. "One of the first things we have to do, a great way to begin to change, is to be more honest about saying what you think."

The problem is, saying what you think in Cuba can be dangerous. In 2002, Cuba imprisoned dozens of journalists who declared themselves dissidents and published criticisms of the regime -- many are still there. Most Cubans are so afraid of being labeled a critic that they are reluctant to utter the words "Fidel Castro" in public. Instead, they silently pantomime stroking a beard when referring to their leader.

Direct Writing

Ms. Sánchez's writing is direct. On Oct. 5, she wrote about Mr. Castro's regular newspaper editorials, which usually focus on international politics rather than the problems of Cuba.

"The latest reflections of Fidel Castro have ended my patience," she wrote. "To try to evade or distance oneself from our problems and theorize about things that occurred thousands of kilometers away, or many years ago, is to multiply by zero the demands of a population that is tired, disenchanted and in need today of measures that alleviate its precariousness."

The fact that Ms. Sánchez has avoided jail is a source of great intrigue for global Cuba watchers and the Cuban exile community in Miami. Some experts say it signals new tolerance by Raúl Castro, who has taken over day-to-day leadership from his brother because of Fidel's deteriorating health. Since taking temporary power in July 2006, Raúl Castro has called for an "open debate" on the country's economic policies, and promised agricultural reforms to bolster the food supply. Cuba experts debate whether Raúl's promises suggest a true re-examination of Cuba's economic model, or are simply rhetoric.

Others, especially the exile community, can't quite believe Ms. Sánchez gets away with what she does. They wonder if she is an unwitting dupe -- or a complicit agent -- in a campaign to make Raúl Castro appear more tolerant as he seeks greater foreign aid.

"From the bottom of my heart, I want her blog to be legitimate and be the seed that grows into something in Cuba," says Val Prieto, a 42-year-old Miami-based architect who edits an anti-Castro blog called Babalu. "The reason the exile community is wary is that we've been bamboozled time and time again. You never can tell when it comes to Castro."

There may be a simpler explanation. Some experts say Cuban authorities are mainly concerned about what people on the island think, and since the vast majority of Cubans don't have Internet access, the government is less alarmed by a Web site available primarily to outsiders.

Taken Aback

Ms. Sánchez seems surprised by the debate. "It's funny, but it seems that the only way some people will believe I am authentic is if I am thrown in jail," she says. "I'm not sure I want to provide that kind of proof."

It's easy to see why Ms. Sánchez is such a mystery. In a place known for bombastic gesticulation, she makes her points with subtle wit. She is passionate about Cuban culture, but doesn't care for signature elements like baseball and cigars. Though a critic of the government, she hasn't affiliated with the island's official political opposition. Perhaps most surprising on an island that many risk their lives to flee, she left Cuba in 2002, only to return two years later.

Her blog is called Generación Y (www.desdecuba.com/generaciony²). The title refers to a fad for names starting with "Y" that began in the 1960s. Cuba's boxing team, for instance, has members named Yoandry, Yuciel, Yampier and Yordenis. Roughly between 25 and 40 today, people in this generation are the offspring of the revolutionaries. Weaned on Soviet cartoons and Communist slogans about a "luminous future," they came of age amid shortages of food, clothing and soap as the economy crumbled.

This group will play a critical role in forging a new Cuba once Mr. Castro is gone. Many expect a showdown between Ms. Sánchez's broadly disillusioned generation and an older group of hard-liners who will try to keep a version of the Castro model going after he dies. Her writing has become required reading for Cuba experts seeking insight into the psychology of this group. Her blog received a half-million hits in October.

The blog reads like her interior monologue as she goes through her routine in Havana: Collecting the daily ration of bread (one bun per person per day), taking her son to school, and running errands -- often trekking on foot to avoid riding the "camel," a bus pulled by a soot-belching tractor-trailer cab.

Rundown Houses

Walking through the city on a recent day, she became lost in thought looking at graffiti and later at a market stall where oil and vinegar are sold in plastic bags. She noticed growing numbers of canine police on Havana's streets, and concluded crime is rising, though statistics are seldom reported. Away from the brightly painted tourist center of "old Havana," Ms. Sánchez walked along streets where once-impressive homes lie in disrepair. She commented on how few new buildings have been built since the 1959 revolution.

Born at the height of the revolution, she was a "pioneer" – Cuba's answer to the Scouts -- and recited its pledge: "I am a pioneer for Communism, We will be like Ché."

"The homes in this city speak for themselves," she said. "They are the best example of how things have functioned in reality, despite all the political propaganda."

A recurring feature is her 12-year-old son's school. Recently, he participated in a military shooting exercise there. Her son enjoyed playing soldier, but she was outraged. In another entry, she described how parents congregate at the schoolyard at lunchtime to secretly pass food to their children who don't get enough to eat. She described her sadness at seeing children whose parents who don't turn up and will go hungry.

An Oct. 22 entry talked about how her son's teacher told the class that one student had been secretly designated an informer -- charged with keeping a list of good and bad kids that the teacher could use to mete out punishment.

"So young, and these children experience the paralysis generated by the feeling of being watched," she wrote. "I look around me and confirm that the successive irrigations of paranoia have worked. Our fears are populated by CIA agents and members of the secret police."

Fear and Paranoia

Ms. Sánchez believes fear and paranoia are key elements in the Castro government playbook to stay in power. Fear of Cuba's own secret police and fear of an imminent U.S. invasion are perennials. Fear leads Cubans to restrict what they say and do, Ms. Sánchez says. For instance, while Cuba's hotels and resorts are for tourists only, there is no law that a Cuban citizen can't walk into a hotel and use the Internet cafe. Hotels, however, generally bar Cubans from entering, to avoid running afoul of authorities.

Writing her blog is one way to shed her "internal policeman," Ms. Sánchez says. "I am trying to push the limits, to find the line where the internal limits end and the real limits begin." She thinks more Cubans are pushing nowadays too. Lately, in bread lines and other informal gatherings, she's witnessed Cubans publicly complaining about things like corruption, low wages, or the decaying health system.

She recounts how eight strangers in a pre-1959 taxi began to talk freely of their discontent. But the complicity ended abruptly when the taxi arrived at its destination.

"Perhaps it's just wishful thinking that things are changing that has me noting a certain tendency toward collective catharsis," she wrote on Sept. 30. "Whereas once there were shrugged shoulders and turned faces, I now see fingers pointing out the problems, and mouths emanating inconformity."

The reason people feel more confident about openly complaining is economic, she says. The downturn of the early 1990s forced Cuba to allow some private enterprise, such as letting people open small restaurants in their living rooms or rent out rooms. That, plus cash transfers from Cuban exiles, has made locals less reliant on the government for jobs. A measure of economic independence has brought a measure of political independence, she says.

But there are limits. In a May 22 entry, she recounts how eight strangers in the anonymity of a pre-1959 Chevrolet taxi began to talk freely of their discontent. But the complicity ended abruptly when the taxi arrived at its destination. The passengers departed, ignoring each other and resuming their public silence.

Ms. Sánchez grew up in Havana, the daughter of a railroad worker and a housewife. As a girl, the egalitarian future of economic equity envisioned by the revolutionary Ché Guevara seemed in reach. She was a "pioneer" -- Cuba's answer to the Scouts -- and recited its pledge: "I am a pioneer for Communism, We will be like Ché."

The family was plunged into poverty by the collapse of Cuba's economic sponsor, the Soviet Union. In 1991, Mr. Castro declared a "special period" of drastic reductions in food and other rations. Average daily caloric intake fell by 40%. Eventually, optic neuritis, a rare eye disease caused by poor nutrition, swept the island.

When friends got together during those times, Ms. Sánchez recalls, a single topic dominated conversation: food. To stave off hunger pangs, Ms. Sánchez gobbled spoonfuls of sugar. Scarcity of soap, shampoo and sanitary napkins added to the trauma for an adolescent becoming aware of her body. Many basics were scarce.

"You wanted to go out, but you had no shoes," she says.

The special period transformed Ms. Sánchez from true believer to cynic. She recalls witnessing her parents fall into despair -- a shared experience for many in her generation.

"It was a deep psychological blow for our parents, because they'd given their best years to the revolution and things weren't as they'd imagined," she says, "My parents suffered the desperation and panic of not being able to give their children enough to eat."

Ms. Sánchez attended one of Cuba's revolutionary rural high schools, created to forge a new generation in the atmosphere of farm life. The school was named for the Socialist Republic of Romania -- even though Romania's socialist government had fallen by the time Ms. Sánchez arrived in 1990. At school, students hoarded scraps of food under their mattresses, attracting rats to the bunks at night, she says.

Ms. Sánchez says she was eventually admitted to the University of Havana's Faculty of Philology -- the study of language and literature -- where she nurtured a love for Latin American writers. But her thesis topic -- dictatorships in Latin American literature -- caused a scandal. Her academic career ended before it began.

"The thesis wasn't overly critical, but the mere act of defining what a dictatorship is in an academic paper made people really nervous, because the definition was a portrait of Cuba," she says.

She met and fell in love with Reinaldo Escobar, a Cuban journalist nearly three decades her senior. In the 1980s, he was forced out of journalism after trying to publish a few critical articles. He began a new career teaching Spanish to tourists, and developed a network of friends in Germany and Switzerland. Ms. Sánchez and Mr. Escobar had a son in 1995.

In 2002, Ms. Sánchez obtained government permission to leave and moved to Switzerland, thinking she'd never return. She was later joined by her son and husband. Cuba allows some people to leave the country each year.

But the family decided to return to Cuba in 2004, after Ms. Sánchez's husband, who recently turned 60, had trouble finding work. "It's much easier for someone my age to start over," she says. "I didn't want to condemn him to a life of informal labor at that age, and breaking up the family was unacceptable."

Returning to Cuba was a difficult decision says Ms. Sánchez. What made it possible, she says, is a deep attraction to the beauty of the island and the energy of its people. "I came to some kind of internal understanding that I am going to go back, but I am not going to accept things as they are," she says. "I am going to try to do something."

In addition to publishing her blog, she talks freely about taboo subjects. She tells neighbors that she doesn't vote, a shocking admission in Cuba. She isn't a member of any of Cuba's quasi-compulsory political organizations.

"There are many ways to pretend in Cuba: you can say things that you don't believe, or you can stay quiet about the things you don't like," she says. "I have the tranquility of being able to look at my son and he knows that I don't fake it."

At the same time, she tries not to cross a line that will give the government a reason to shut her blog down. She uses only public Internet sites, instead of trying to set up an illegal Internet link from home, as some Cubans do. The family lives on between $20 and $60 a month, she says, earned from working with tourists. She confines her writing to the Web. Critiques published on paper are considered propaganda, while the Internet is a gray area.

Still, there is no guarantee that Ms. Sánchez's activities won't land her in legal trouble. Even if jailed, Ms. Sánchez says she would find ways to publish her blog. "You have to believe that you are free and try to act like it," she says. "Little by little, acting as though you are free can be contagious."

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