Who was Rey Diaz in the Three-Body Problem?
Manuel Rey Diaz was the President of Venezuela and one of the four Wallfacers chosen to devise secret strategies against the Trisolaran invasion. Among the four, he was the strongman politician, a Latin American leader known for iron-fisted rule and a willingness to make decisions ordinary people could not stomach. That reputation is exactly why the Wallfacer Project selected him. Where the others reached for cosmic sociology or neuroscience, Rey Diaz reached for the oldest and bluntest form of power: raw physical destruction.
What was Rey Diaz's real Wallfacer plan?
His true plan was to push the planet Mercury out of its orbit and into the Sun the moment humanity's defense line collapsed, triggering a chain reaction meant to destroy the entire solar system. The public version of his plan was a defensive one: stockpile enormous numbers of stellar-grade hydrogen bombs as humanity's core space arsenal, the largest weapons program in history. But the bombs were never the point. They were the tool for a doomsday move, a way to make sure that if the Trisolarans took the solar system, there would be no solar system left to take.
Crucially, this was not deterrence. Cold War mutual assured destruction only works if the threat is public, because its whole purpose is to stop the other side from striking first. Rey Diaz never intended to announce his plan at all. That makes it darker than the later dark forest deterrence that Luo Ji built, which at least put the threat on the table. Rey Diaz did not want a negotiating table. He wanted a dead man's switch.
Could pushing Mercury into the Sun actually destroy the solar system?
No, and the physics is worth taking seriously because this is where the scheme really lives or dies. Mercury orbits the Sun at about 47 kilometers per second, and to make it fall inward you would have to cancel a large fraction of that orbital velocity. The energy required is astronomical, far beyond any conceivable stockpile of hydrogen bombs, even one that used up every gram of fusion fuel on Earth. Aiming a planet at the Sun like a billiard ball is narrative romance, not engineering.
The chain reaction is even shakier. The novel imagines Mercury's fall knocking over the first domino, with Venus and then Earth spiraling in after it. Real celestial mechanics does not work that way. Each planet's orbit is dominated overwhelmingly by the Sun's mass, and Mercury is only about one six-millionth of that mass. The gravitational coupling between planets is far too weak to cause an avalanche. Remove Mercury and Earth's orbit barely notices.
Why did Rey Diaz's plan fail?
His Wallbreaker exposed the true intent, and the moment a scheme to destroy everyone's home became public, Rey Diaz turned from strategist into humanity's enemy. He fled back to Venezuela expecting shelter and was stoned to death by his own people, one of the bitterest ironies in the trilogy. The deeper lesson is the same one the Wallbreakers kept teaching: the plan's literal physics never mattered as much as its meaning. It was never a science project. It was a political gesture of despair, a hostage-taking aimed at an entire civilization, and its power lay entirely in the sentence I would rather destroy it all than let you have it. Compared with Luo Ji, who turned destruction into a credible and public switch, Rey Diaz held only a bomb no one could control. One was game theory. The other was a tantrum, and that difference is the hidden line separating the four Wallfacer plans.