HAVANA, Cuba — Fidel Castro’s return has been almost as complete as his absence.

When he fell ill and nearly died four years ago, Castro disappeared from public view entirely, the status of his health treated as a state secret.

Now he’s back, and once more an everyday fixture in Cuban homes, as government television cameras track his campaign to warn the world of a coming nuclear war.

Given the all-or-nothing character of the white-bearded commandante — who turns 84 today — it’s no surprise that Castro’s reemergence has left many Cubans and Cuba-watchers wondering how far the comeback will go. Has he returned to rule Cuba again?

Castro himself addressed the question in an interview with a group of Venezuelan reporters broadcast on Cuban television Monday night.

“My job is to draw attention to topics and events and let others decide,” Castro explained. “You should understand that our (leaders) are not people I should order around or tell what to do. I want them to think for themselves.”

The division of labor between Castro and his 79-year-old brother Raul — who took over Cuba’s leadership temporarily, then permanently — has hewn to clear boundaries so far. Fidel has said virtually nothing about Cuba’s domestic problems since his return to public life, even though he spent nearly five decades shaping the island’s now-rickety socialist system.

Instead, he sticks to world affairs, and specifically, the ardent belief that a U.S. and Israeli confrontation with Iran is imminent, and it will lead to an atomic exchange. He convened a special session of Cuba’s parliament over the weekend to discuss the theory, urging delegates to help convince U.S. President Barack Obama not to push the button.

“Obama won’t give the order to attack if we persuade him not to,” Castro told the audience. “A lot of people are with us in the effort.”

Castro’s devotion to the topic is becoming reminiscent of his old campaigns — for the return of 6-year-old shipwreck survivor Elian Gonzalez in 2000 or the failed push to harvest 10 million tons of sugar in 1970. Cuba’s state-run media follow Castro’s lead and cover the nuclear theme exhaustively, without a single dissenting voice to question the likelihood of such a scenario.

Castro’s detractors say his antiwar crusade is a smokescreen, loaded with underlying messages.

Dissident writer and activist Miriam Leiva said Castro’s silence on his brother’s tentative economic reforms and efforts to improve relations with the United States is a signal that he doesn’t approve of such changes.

“I think he chose this moment because it was obvious something was moving in the country,” she said, citing the ongoing release of dozens of political prisoners as part of an unprecedented dialogue with the island’s church leaders.

Also, she said, “he can’t be away from the spotlight.”

Even if Castro doesn’t talk about Cubans’ everyday concerns, “he wants people to feel he’s there, he’s not away, and that he could have a say,” she said. “But it’s not possible for him to come back the way he was before, because Raul has put all of his own people in place.”

It’s not clear what effect Castro’s return might have on the latest attempts to improve U.S.-Cuba relations. The Obama administration is expected to further ease Cuba travel restrictions in the coming weeks, allowing more Americans to visit the island and more U.S. airports to set up Havana flights.

In his Monday appearance, Castro also backed off from previous assurances that the “Cuban Five,” a group of intelligence agents held in U.S. prisons, would be freed by the end of the year. He acknowledged to the Venezuelan reporters that his prediction had unsettled some in the government, but stood by the claim that they would return before December.

Few Cubans said they were surprised by Castro’s return, and as the novelty of seeing him on television again has worn off, several said his voice already seemed familiar, as if he’d never left.

Sitting along the Havana seawall to escaping the heat on a recent night, Juana Maria Rodriguez said she was glad to see Castro back, and she took his nuclear warnings quite seriously. “It would bring so much damage to the world,” she said, “humanity would be destroyed.”

Rodriguez said there was never any confusion for her about who’s in charge. “Fidel is the leader of this Revolution,” she said, “even if that’s not what they say publicly.”