Admiral Tom Wilson, head of the Defense Intelligence Agency, says the 74-year-old communist dictator may be preparing a cyberattack against the United States.

Wilson told the Senate Intelligence Committee during a public hearing Wednesday that Castro's armed forces could initiate an "information warfare or computer network attack" that could "disrupt our military."

The panel later went into closed session to discuss classified material.

Sen. Ron Wyden (D-Ore.) asked in response: "And you would say that there is a real threat that they might go that route?"

Replied Wilson: "There's certainly the potential for them to employ those kind of tactics against our modern and superior military."

He said that Cuba's conventional military might was lacking, but its intelligence operations were substantial.

The partly classified hearing is an annual event -- and an important one: It represents this year's World Threat Assessment discussion. That's a chance for the intelligence committee to set its agenda for this session of Congress and hear from senior intelligence officials about the latest national security threats.

In addition to the aging president of Cuba, witnesses and senators both cited encryption as another technology-related threat during a far-ranging discussion that also encompassed nuclear, biological and chemical weapons.

Sen. Richard Shelby (R-Ala.), the committee's hawkish chairman, said that the classified hearing later in the day would "explore the challenges posed by, among others, the proliferation of encryption technology, the increasing sophistication of denial and deception techniques, the need to modernize and to recapitalize the National Security Agency, and other shortfalls in intelligence funding."

Shelby has been a vehement opponent of any proposal to remove encryption export regulations. In 1998, he said "the effects on U.S. national security must be the paramount concern when considering any proposed change to encryption export policy."

He is currently the co-chair of the Congressional Privacy Caucus. Last week, Shelby sent out a press release saying, "Personal privacy is one of the most important issues that we must confront in the new world of the information economy."

At the January 1998 World Threat Assessment hearing, the talk also turned to encryption. "I don't want to tell some father that we've lost a child because we couldn't break the telephone conversation or we couldn't get to a storage disk or something like that," FBI deputy director Bob Bryant told the panel at the time. "And that's all we're saying."

Also warning of the dangers of encryption products, which let users shield communications from prying eyes, was CIA Director George Tenet, who has frequently spoken out against the technology in the past.

Tenet testified that terrorists such as Osama bin Laden are now using the Internet and encryption to cloak communications within their organizations. "So, you know, you recruit people on Internet sites, and you use encryption," Tenet said. "You move your operational planning and judgments over Internet sites' use of encryption. You raise money."

His comments come as a series of newspaper articles have highlighted how bin Laden allegedly uses encryption -- and a variant of the technology, called steganography -- to evade U.S. efforts to monitor his organization.

Tenet said that bin Laden "and his global network of lieutenants and associates remain the most immediate and serious threat" to America.

And what about Castro? It might seem odd to view a country best known for starving livestock, Elian Gonzalez and acute toilet paper shortages as a looming threat, but the Pentagon seems entirely serious.

The DIA's Wilson said: "Cuba is, Senator, not a strong conventional military threat. But their ability to ploy asymmetric tactics against our military superiority would be significant. They have strong intelligence apparatus, good security and the potential to disrupt our military through asymmetric tactics."

Asymmetric tactics is military-ese for terrorist tactics when your opponent has a huge advantage in physical power.

Shortly after those comments, Shelby adjourned the hearing until the afternoon, when it resumed behind closed doors.

This week's drumbeat of criticism about encryption and steganography from within Washington's national security circles may hint at congressional efforts to impose additional restrictions on the technologies. President Clinton relaxed -- but did not remove -- rules governing the export or Internet distribution of encryption products.