Not a lot of links today.
Let me ruminate on Starkiller Base.
A civilization that can build a Starkiller Base would never need it.
What I mean by this. We’re talking about a work of massive planetary engineering. Assuming an Earth-size planet, the trench alone would be thousands, if not tens of thousands, of miles long. It looked that they cut down into the mantle, if not the core — without triggering massive lava eruptions or rendering the planet uninhabitable.
The resources required to create this were immense. Perhaps it was all done by robots, in which case the resources for the robots had to be harvested, the robots themselves had to be built, etc. I imagine the construction droids on this project might have been Von Neumann Machines; they built copies of themselves using the refuse of the planet’s demolition.
If you can do all that, you don’t need a weapon that can destroy planets. You could build your own instead. You could take apart a solar system and build a Niven Ring, a Dyson Sphere, or an Alderson Disc. You don’t need a Starkiller Base to demonstrate your power; the fact that you can engineer a planet on that scale is a demonstration of your power.
Unless the Republic is capable of an engineering feat on the scale of Starkiller Base, there is no competition; the First Order would simply outclass the Republic, and planet after planet would fall into the First Order’s sphere of influence.
That’s true power.
The weapon itself is superfluous.