Robert Stadler realizes that regardless of the outcome of events in Washington, he has no place there. If Galt wins, Stadler will be rejected as a traitor to the mind's cause. But if the looters win, he'll be subordinate to a pack of ignorant dolts whom he despises. In the chaos of increasing civil war, Stadler needs to carve out a kingdom of his own. He drives to the Project X site in Iowa, intending to employ the deadly weapon as a means to establish his own fiefdom, but Cuffy Meigs beat him to it. In the ensuing power struggle, the weapon is activated, cutting a swath of destruction for hundreds of square miles, killing everybody at the installation, including Stadler.
The looters take Galt to the State Science Institute, where they use torture in an attempt to force him to fold. Dagny calls Francisco, who left her a number for such a contingency. While she prepares to go in search of Galt, a railroad engineer contacts her, letting her know that the vital Taggart Bridge spanning the Mississippi was destroyed by the Project X explosion. Dagny says that she doesn't know what to do about that problem, and she leaves to join Francisco.
At the State Science Institute, the looters torture Galt. When the torture device breaks down, the looters don't know how to repair it. Galt instructs them how to fix the device. James Taggart, in the act of trying to break Galt, realizes that his life is dedicated to the destruction of the good, and in that moment he recognizes his own unmitigated evil. He collapses, unable to live with such knowledge.
Robert Stadler, the genius turned feudal baron, dramatizes the principle that men seek to live by either mind or force. Holding an elitist belief that only a select few are interested in ideas and that most men are irrational brutes, Stadler necessarily believes that reason is impotent in dealing with people and that only intimidation and force are effective weapons. He is then driven by the logic of his theory to become a looter, a power seeker, and ultimately, Galt's worst enemy. The form of his death is not ironic; his death is the exact end dictated by the logic of his life. He placed his mind in service to the brutes and is killed by the weapon that his research created for them.
Galt, knowing the logical inevitability of Stadler's end, refuses to turn his mind over to the purveyors of force. He uses his mind only to create and defend the values necessary for life on earth. Even the help that he gives the looters to repair the instrument of torture is an action taken in defense of himself and against the looters, because he shows them that they're dependent on him even for the most evil purposes. The irrational live off the men of the mind, and Galt drives this point home to them. Galt, the preeminent man of the mind, is the generator of progress and prosperity.
Dagny, knowing that the looters are willing to torture and kill Galt, finally understands their true nature. Previously, Dagny believed that the looters had a will to live, but were mistaken about how to do so. Now she realizes that in forsaking the mind in favor of brute force, they've given up on human life. They support a code of death: Destruction is all that their policies can lead to, and destruction is their goal. Their willingness to torture Galt is significant because Galt represents the mind. No man who would torture the mind can claim life as his goal. Dagny sees the irredeemable evil of the looters and the necessity to withdraw her mind from their system. Dagny joins the strike with the act of walking away from the Taggart Bridge disaster.