system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Who was more important to Palpatine, Vader or Tarkin?
gpt
Vader by a mile. 

Tarkin was incredibly effective and efficient, and an excellent asset to the Empire; he ruled the Outer Rim as Grand Moff, and it was his Fear Doctrine that led to the creation of the Death Star. 

But in the end, he was ultimately expendable. His position could be filled by others, or broken into subsections by lesser ranked officers. Vader however, is a one-of-a-kind enforcer and military leader, who could do the Emperor’s dirty work better then anyone else. Palpatine could always get another political head, but not a super powerful apprentice to do his bidding.