system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Why was the death star built when you could just carpet bomb planets using giant space ships?
gpt
It's about fear.

A fleet of ships. That's an understandable thing.  Something you can get your head around.  A fleet comes to glass your planet, you think maybe you can fight.  Maybe you can drive them off, or maybe there will be enough left after to rebuild.  

A moon-sized space station that can reduce your whole planet to rubble in an instant?  There's no reaction to that thing except fear and desperation.  At least that was the idea.

There's other advantages too though.  With a fleet, you have to trust your Admirals and Captains to operate loyally without you.  Something like the Death Star, one strong leader can control that directly.