If Mace Windu had killed Palpatine in Revenge of the Sith , the immediate and long-term consequences for the galaxy would have been profound and complex.

Immediate Consequences

• Political Fallout: Palpatine was the widely recognized Supreme Chancellor of the Republic, so his sudden death at the hands of a Jedi would have shocked the galaxy. The Jedi would have to publicly reveal that Palpatine was a Sith Lord who orchestrated the Clone Wars, which would cause widespread disbelief and accusations of conspiracy among the Senate and the public

• Mace Windu's Fate: Windu would likely face arrest and trial for killing a political leader, despite acting to stop a Sith threat. However, security holograms showing Palpatine's Sith identity and his killing of other Jedi could potentially exonerate Windu, allowing him to avoid imprisonment and preserve his reputation

Impact on Anakin Skywalker

• Without Palpatine's survival and influence, Anakin would not have turned to the dark side as Darth Vader. Instead, he might have remained a Jedi, possibly with guilt and confusion over the violent events

• However, Anakin’s fear of losing Padmé and the loss of Palpatine’s promise to save her could still cause inner turmoil, potentially leading to other struggles with the dark side

Broader Galactic Implications

• Jedi and Republic: The Jedi would have to explain and justify their extrajudicial killing of Palpatine, which might damage their public standing and political influence. Many in the Senate might view the Jedi as overstepping their authority, exacerbating distrust

• Sith Threat: Killing Palpatine would remove the immediate Sith threat, but Palpatine had spent over a decade manipulating the Senate and Republic institutions. His political control was so entrenched that even his death might not immediately restore the Republic or prevent further chaos

• Order 66 and the Clone Wars: Without Palpatine to issue Order 66, the Jedi might avoid the mass purge. The Clone Wars could end differently, potentially with the Republic surviving in a more stable form

Summary

While Mace Windu killing Palpatine would have prevented the rise of the Empire and Anakin’s fall to the dark side, it would have plunged the galaxy into political turmoil. The Jedi would face legal and public relations battles, and the Republic would struggle to recover from a decade of Palpatine’s manipulation. Anakin’s path would be uncertain but potentially less dark. Overall, the galaxy’s fate might be better in the long term but chaotic in the short term