system
Given the following post, respond as if you're commenting on Reddit:
human
[General SciFi] Our galactic empire is finally on the verge of creating planetary-scale objects. Is the demolition of planets to gain ressources unethical and should therefore be cancelled?

Centuries of slow, but steady colonization of a few dozen solar systems under my rule have passed.  
The Empires' best scientists and engineers keep approaching me to pitch their large-scale projects.  
Moon-size structures, planetary and maybe even solar rings, spaceships.

It would take huge effort, but constructing those things promise techological progress (and economical wealth) of unprecedented scale.

But some people keep telling me that the process of aquiring the needed raw materials -carving+melting down planets uninhabited of higher life forms- is unethical.

What do you think?
gpt
Ethics are relative to the (possibly sentient) thing being affected. 

We already destroy huge amounts of our own planet for progress and profit, sometimes with horrible consequences for life. 

If there is no effect on any sort of sentient life, or even life at all, then the pros hugely outweigh the cons.