Warning! SPOILERS ahead for The Walking Dead season 9, episode 12, as well as comics.
Daryl just made a big mistake on The Walking Dead, and it's possible that what he's done will lead to war. The Walking Dead season 9 has the survivors up against a new enemy, the Whisperers, and they are unlike anything they've faced before.
Along with the introduction of the Whisperers, The Walking Dead season 9 finds the different communities - Alexandria, Hilltop, The Kingdom, and Oceanside - at odds with one another, with Alexandria in particular isolating themselves from the other communities. To foster a new sense of camaraderie among the communities (and renew trade between them), The Kingdom is holding a fair, and now that Alexandria has finally agreed to send a delegation, it appears the fair will see members from every community coming together. However, if the fair on AMC's The Walking Dead winds up being anything like the fair in The Walking Dead comics, then it is doomed to end in tragedy - and it might all be Daryl's fault.
In The Walking Dead season 9 episode 11, Daryl was leaving Hilltop in pursuit of Henry after he'd taken off after Lydia and the Whisperers. Accompanied by Connie, in The Walking Dead season 9 episode 12, "Guardians", audiences see them them catch up with the Whisperers as they're feeding a herd, attacking a pair of them in order to steal their masks. Daryl and Connie then lead the herd towards the Whisperers' camp, using the chaos of the herd's attack to find Henry. Once they find him, however, Henry refuses to leave without Lydia. And so, with their chance to escape quickly slipping away, Daryl makes a decision he's sure to regret - stealing Alpha's daughter yet again and most likely kicking off the conflict that becomes the Whisperer War.
How The Whisperer War Starts In The Comics
In The Walking Dead comics, the Whisperer War kicks off when Alpha kidnaps, murders, and decapitates several of the survivors, impaling their reanimated heads on pikes to mark the border with Whisperer land. She does this to send a message: crossing the border in to Whisperer land will be considered an act of war. Alpha kidnaps her victims from the fair - stealing people right out in the open - and the attack is a potent reminder of the sort of danger the Whisperers pose. In response, Rick and the outraged survivors form a militia and begin training, knowing it will only be a matter of time before war breaks out.
That moment comes when Negan escapes from Alexandria, forcing Michonne and Aaron to go after him. Soon, both Negan and his pursuers wind up on Whisperer land, at which point, Michonne and Aaron come under attack from Beta and a group of Whisperers. They barely escape with their lives but the damage is already done - and the Whisperer War is on.
How Saving Lydia Can Start The Whisperer War
AMC's The Walking Dead is handling the buildup to their own Whisperer War a little differently, and it seems all but certain that Daryl's action in "Guardians" will be what kicks things off. Having already avoided a fight with the Whisperers by returning Lydia to her mother, Daryl's decision to rescue her along with Henry undoes that uneasy truce. Now, Alpha will want revenge not just for the Whisperers killed in the herd's attack, but for them stealing what she believes belongs to her - her daughter.
The setup is different than what happens in The Walking Dead comics, but it's surely leading to the same outcome. When the fair takes place at the Kingdom, Alpha and her Whisperers will infiltrate the festivities to kidnap the survivors they will kill, beginning the war. And while originally we theorized it was Ezekiel's mission to retrieve a projector lamp - a trip that took them into land marked by mysterious symbols - that would bring the Whisperers to the fair, it now seems more likely that Daryl's decision to rescue Lydia is the cause. (Though, it may be still be that their trip is what alerts the Whisperers to the Kingdom's location.)
Only time will tell whether or not The Walking Dead will see Alpha impaling the heads of her victims on pikes, but she is certainly coming to the fair seeking her revenge. Once she does, however, she is also sure to unite The Walking Dead's communities in a way the fair never could - again giving them a common enemy to fight against.
The Walking Dead season 9 airs Sundays on AMC.