The First Battle of Geonosis occurs near the end of Star Wars: Episode II - Attack of the Clones. There's a scene in the execution arena where the Jedi are surrounded by the droid army. Dooku offers the Jedi a chance to surrender so that their lives are spared. The Jedi refuse, and at the last moment before they are destroyed, the clone army shows up and saves the day.
If Darth Sidious's goal is to eliminate the Jedi, then why didn't he execute Order 66 right then and there at the First Battle of Geonosis? The Jedi were surrounded and surely would have been destroyed. Even Yoda was on one of the ships carrying in the clones. Why did he wait 3 years to give Order 66? Surely he didn't require any sort of bureaucratic permission: in Episode III, Darth Sidious simply gives the command ("Execute Order 66") and the clones comply ("It will be done, My Lord").
It seems possible to construct plausible reasons why Darth Sidious might have wanted to wait:
- Sidious was waiting to lure Anakin to the dark side.
- Some Jedi may have stayed behind instead of going to Geonosis. Those Jedi would have continued the fight against the Sith.
- Palpatine was worried that the Senate was still too strong and might turn on him.
- Palpatine wanted to build up the clone army to even larger numbers, and continuing the war was necessary to achieve that goal.
But what is the actual evidence that the movies themselves provide?
This question was posed here, but the answers are not completely satisfying for someone looking for a movie-based explanation. The list of possible explanations (above) draws heavily from that scifi thread. But here are the more specific issues I have with some of those answers.
- The first answer, which was accepted, cites the novel Star Wars Republic Commando: True Colors.
- The second answer, which was the most upvoted, states: "he was able to use the Jedi as tools to help eliminate those that stood in the way of his ultimate goal," but I'm not sure which specific people from the movies this is referring to.
- The third answer states: "One more reason: Order 66 works because the Jedi have come to trust the Clone troops implicitly. This trust would have to be built first." But this doesn't address the fact that, in the movie, the Jedi were surrounded by the droid army and had all but been defeated. Giving the code at that time would have eliminated the Jedi, assuming they were all at the battle.
- Another answer states: "Simply, Palpatine didn't want to lose Anakin. Even if Anakin would have been isolated from Order 66, he would never had gained loyalty of Anakin. And, Anakin would have turned against him for killing Jedi." But Sidious would want Anakin in order to achieve his top priority of eliminating the Jedi and gaining total control. If he executes Order 66, then now (a) the Jedi are all gone, (b) he has a massive army of both droids and drones at his disposal, and (c) an assistant (Dooku) who is extremely powerful. His goal is achieved, and there's no need to use Anakin as a means for that goal.