To YouTube images of students being beaten and killed in the streets, Mr. Maduro responded with claims that his country is in the grips of a “cybernetic war.” (Many people agree with him.)

And when the president decided that some CNN reporters’ coverage of the demonstrations was too favorable to the protesters, he threatened to suspend their broadcasts and expel the network’s principal anchor.

In Venezuela, the power of ideology is easily understood: The vast spell cast by Mr. Chávez endures, and millions of people remain convinced that Chavismo in fact did good works. There is a practical side to that loyalty as well, since many people depend directly on financial and material aid from the government while private enterprise and investment continue to languish.

Outside of Venezuela, Latin American support for Chavismo springs from two sources: the enduring prestige of the Cuban Revolution, and the cold economic calculations of various countries that are carefully positioning themselves for the coming post-Castro years.

Political backwardness in Latin America is explained mainly by loyalty to what is largely a myth: that social revolution, not democracy, is the preferred route. Our political idols have not been democrats, but rather redeemers, like Fidel Castro. In fact, Cuba continues to be the nerve center of progressive ideology in Latin America. As a testament to its weight, almost every Latin American president attended the summit late last month in Havana of the Community of Latin American and Caribbean States, at which Fidel Castro was hailed as the “political and moral guide.”

But the material interests of Venezuela’s Latin American brethren are also quite important. Brazil, for example, sees economic opportunities opening up in Cuba after the Castro brothers leave the scene and doesn’t want anything to get in the way. Hence Brazil’s support for stability in Cuba but also for safeguarding ties between Havana and Caracas (Venezuela supplies Cuba with oil). Thus we have the odd situation of President Dilma Rousseff of Brazil, who was tortured as a student by the Brazilian military, defending, or at least tolerating, the armed repression of students in Venezuela.

But the young people risking their lives to demonstrate against their government aren’t especially interested in geopolitics. What they know is that democratic progress needs more than just elections to move it forward; it requires full freedom of speech in the media. Just how long this particular contest will last between the brute power of government and those who would push democracy further along is anyone’s guess. In any case, it will be played out on the streets of Venezuela.

Enrique Krauze is a historian, the editor of the literary magazine Letras Libres and the author of “Redeemers: Ideas and Power in Latin America.” This article was translated by Hank Heifetz from the Spanish.