Star Ocean: The Last Hope/Headscratchers

How the hell does an entire planet run out of energy in 1948? Did they seriously run out of coal and wood to burn? They couldn't harness solar, wind, geothermal, or hydro power!?
- It's implied that humanity fucked up Earth that badly. Edge mentions in one Private Action that Earth is so polluted that you can't see the stars in the sky any more.
  - Yet they have enough resources to create a space fleet, as opposed to, say, feeding people, or cleaning the sky.
  - Since it was nuclear annihilation, the concern Earth faces isn't a lack of metal or other materials needed to make things like starships and moonbases, it's a lack of things like food, breathable air, and clean water, something that would presumably take a very, very long time to fix. We never hear about whether or not people ARE working to clean the Earth (and judging from later installments in the Star Ocean series, they at least make it livable, if still dirty and crowded.) because the story focuses on the people sent to explore other worlds for colonization.
- Also, the 1948 and the out-of-resources were unrelated. The people of 1948 wanted stuff to win the cold war, whereas the people from the main game who want energy and to restore the planet are from, like, the 2070s or something.
Okay, so the earth was somehow cleansed and restored during the course of the game... and no one says a word!
It's nice seeing that major landmarks are nuke proof.
Okay, let me see if I have this right; the normal weapons used by the Earth's soldiers are portable railguns. Fair enough, in the future. Now, these guns are rendered useless by these giant bugs that can sense the electromagnetic emissions of the shots fired by the guns, and in response, create some sort of shield. Edge Maverick is able to fend them off with a sword. Now, I'm no physicist or gun expert, but I'm almost certain that railgun shots travel very freaking fast, which is most likely a Holy Grail amongst gun enthusiasts. A giant spider can sense and block one of these with no physical repercussions, but they can still be defeated by swords that are waved around a bit with a human arm, which is significantly less than the speed of sound.
- Fixed. Thanks to the tropers who bothered to pick up after me.
- I wonder, if the game only needed an excuse for a sword-wielding protagonist, they didn't just do something similar to how they handled SO3, where the protagonist admits that he just plain likes swords, already knows how to use one because it's his hobby, and then never runs into a reason to use something else? Granted, his other reason was to blend in better without toting a gun. But does that really matter at the point of giant magnet spiders?
Why is it, that after Reimi joins the party, the crew members who are guarding the area around the Calnus still holding Railguns, even though they're completely ineffective against the Monsters there?
Isn't it a little odd that the cause of Faize's descent into craziness is the girl he met literally five minutes ago? He must be really sensitive, or mentally/emotionally fragile, or... something.