In House of the Dragon episode 7, Team Green and Team Black begin to solidify as the entire Targaryen clan reunites, and one person is more to blame than anyone else: Viserys. Upon Laena's death, the entire royal family, including Daemon and the newly reinstated Hand of the King, Otto Hightower, convene at Driftmark for Laena's funeral. Here, all the key players in the Dance of the Dragons gather for the first time and the children begin to form their own alliances.
At the ceremony, Rhaenyra's sons Jacaerys (Jace) and Lucerys (Luke) meet Daemon's twin daughters, Rhaena and Baela, for the first time. That night, when Aemond claims the dragon Vaghar before Rhaena has a chance to, Jace and Luke confront Aemond on behalf of Rhaena. Aemond then calls the dark-haired boys bastards, resulting in a fistfight and Luke slashing Aemond's left eye.
When the adults learn of the incident, Alicent finally becomes openly hostile and lunges at Rhaenyra with a Valyrian steel dagger, cutting her hand in retaliation. Viserys' subsequent response to Alicent's pleas for vengeance is telling of the underlying problems in the show: "We’ll speak no more of it." Decades of Viserys trying to please people and keep peace without ever truly addressing the issues and rivalries, despite how bad they're becoming, are what allow them to fester and boil over upon Viserys's eventual death. House of the Dragon, as the name states, is ultimately a show about family drama. The death and violence that follows is a result of the forces within a powerful family dissipating into the political sphere.
Could Viserys Have Prevented The Dance Of The Dragons?
Viserys fails as a king by first failing as a father, weakening his court by allowing his family to fall apart. Starting with his decision to allow the maesters to perform a C-section on Aemma, Viserys has repeatedly exhibited his fatal flaw of withholding communication from those who require it most from him. Even though Aemma would have died with or without the cruel procedure, Viserys could have and should have respected Aemma's right to choose, as Daemon had respected Laena Velaryon's decision to kill herself rather than face a C-section in episode 6. From there on, the house of cards collapses as Viserys continues to suppress issues within his family in what he thinks is the best way to bear all the weight of the crown on his own shoulders—without realizing how Rhaenyra and Alicent and consequently their children have become bitter rivals because of his lack of decisive action.
Aside from Aemma's tragic death, all the violence and suffering in House of the Dragon was preventable. If Viserys had discussed his decision to marry Alicent with Rhaenyra before his announcement to the small council, perhaps Rhaenyra would not have felt as betrayed by both the king and Alicent. Instead, Viserys made the decision to marry Alicent Hightower unilaterally, alienated Rhaenyra from himself, and tore Rhaenyra and Alicent's friendship apart. In the decade to come, Viserys then neglects Alicent's sons instead and turns a blind eye to Rhaenyra's affair with Harwin, as if to make up for his guilt in wronging Rhaenyra. Additionally, if Viserys had allowed Daemon and Rhaenyra to speak openly about their intentions with each other, they could have wed each other and strengthened Rhaenyra's position in court. A union between Rhaenyra and Daemon would have simultaneously granted Daemon the proximity to the crown that he desires, as well as completely avoided the issue of Rhaenyra's sons' legitimacy because of her affair with Harwin Strong.
On Aegon's, Aemond's, and Helaena's part, Viserys fails as a father by withholding from them the reassurance they need as princes and princess secondary to the heir. Otto's paranoid indoctrination of Alicent and her children would have no ground to stand on if Viserys made it clear to his second family that their safety and standing in court is not threatened by Rhaenyra's eventual ascension to the throne, and vice versa. Instead, Viserys decided to sweep all the issues in House of the Dragon under the rug with the hope of them fading away, only to have them culminate in the Dance of the Dragons.