In Star Wars: Episode III - Revenge of the Sith, Order 66.

While not all of that was due to Anakin, as Palpatine no doubt had countless backup plans and had set these events in motion decades prior, Anakin's fall to the dark side and transformation into Darth Vader had a massive impact on these galactic changes. Oddly enough, after years of numerous traumatizing, tragic events dominating Anakin Skywalker's Star Wars timeline, it was Mace Windu's attempt to assassinate Palpatine that fully pushed Anakin to the dark side. 20 years after Revenge of the Sith, I believe I've figured out just why that bothered Anakin so much.

Mace Windu Said Palpatine Was "Too Dangerous To Be Kept Alive"

This Language Undoubtedly Hit Close To Home

Mace Windu wields his purple lightsaber

One of the most significant factors in Anakin's decision to turn on Mace Windu in Palpatine's office was the fact that Palpatine had effectively convinced Anakin that he needed Palpatine—and the dark side of the Force—to save Pé's life. The importance of that manipulation shouldn't be overlooked, but there was more to this scene between Anakin, Mace Windu, and Palpatine than just that. After all, it was a giant leap for Anakin to cut off Mace Windu's arm.

While he may not have dealt the death blow himself, at that point, Anakin knew Palpatine was a Sith Lord. He knew what this move would mean for Mace Windu's life. Yes, Pé was a major factor in that, as Anakin's fears about losing Pé were one of the driving factors in his fall to the dark side. However, I believe that Mace Windu's language and behavior throughout this scene in Palpatine's office actually pushed Anakin over the edge, making him willing to betray the Jedi and allow Mace Windu to be killed by Palpatine.

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Specifically, Mace Windu told Anakin that Palpatine was "too dangerous to be kept alive" and therefore had to be killed right there in his office. In addition to Anakin believing that this was treasonous and contrary to the Jedi way (the latter he was arguably right about), this language echoed the very reasons the Jedi Council had initially rejected Anakin from the Jedi Order—and I believe that triggered this response in Anakin. Even so many years later, Anakin had never really let go of the fact that the Jedi Council's first response was to reject him.

This language echoed the very reasons the Jedi Council had initially rejected Anakin from the Jedi Order—and I believe that triggered this response in Anakin.

Anakin Believed The Jedi Were Wrong About Him

In Anakin's Mind, They'd Been Wrong About Him, And Now They Were Wrong About Palpatine

When Anakin was brought before the Jedi Council as a young boy, the Jedi didn't exactly conceal their concerns about his attachment to his mother, his emotional state, or his age. In fact, not only did Yoda heavily imply that Anakin was dangerous because he had attributes that made him prone to falling to the dark side, but also, no one was more vocal than Mace Windu about their belief that Anakin wasn't right for the Jedi Order. This early rejection and the perception of him as dangerous (which never really went away) continued to haunt Anakin.

I believe this all came flooding back to him at that moment in Palpatine's office, and it influenced how he reacted. Mace's accusation in that confrontation was that Palpatine was too dangerous to be kept alive, just as the Jedi had once believed Anakin was too dangerous to be trained as a Jedi. Because Anakin believed the Jedi—especially Mace Windu—had been wrong about him, he likely believed they were wrong about Palpatine as well. Yes, he knew Palpatine was a Sith, but clearly, his mind was already distorted at that point.

Because Anakin believed the Jedi—especially Mace Windu—had been wrong about him, he likely believed they were wrong about Palpatine as well.

I'm Convinced This Contributed To Anakin's Fateful Decision

Mace Windu's Wording, Along With His Actions, Didn't Do Him Any Favors

Anakin Skywalker and Mace Windu discussing Palpatine being a Sith Lord in Revenge of the Sith

What made this particular situation all the more thorny is that, over the years, more than anyone else, Mace Windu made Anakin feel scrutinized and ostracized. Even with Anakin going to Mace Windu and reporting that Palpatine was a Sith Lord, Mace told him that if it was true, Anakin would have gained his trust. That continued doubt, and the fact that Mace clearly still didn't trust Anakin after more than a decade and after seeing Anakin risk his life every day for the Clone Wars, had to have stung.

It's true that there were multiple factors at play when Anakin chose Palpatine over Mace Windu, and I don't want to discredit the amount that saving Pé was weighing into Anakin's decision. However, in Anakin's split-second decision to cut Mace Windu's arm off and stop him from killing Palpatine, I believe Anakin's history with the Jedi, and with Mace Windu in particular, was a major factor. When Mace Windu said Palpatine was too dangerous to be kept alive, Anakin Skywalker had a knee-jerk reaction, and it cost countless people their lives.