Dr. Device isn't a good mining tool. Also, mind explaining again why the Moon wouldn't work to mine? A cloud of dust or whatever is left after your...intensive mining techniques would still orbit the Earth.
That much matter collapsing on itself leaves a huge gap in the area, needing something to fill it. Earth would gravitate toward it, knocking it out of it's orbit, and killing everyone and everything on it from the stress. Even without that, a lack of a moon would leave Earth without tides, and the following surfer revolt would upset the delicate balance between Dude and Sir. Leaving the world in total anarchy. And, barring either of those, I'll just pretend that the lack of waves would set off a ton of volcanoes and send Earth into another Ice Age.
((Playing fast and loose with physics, social dynamics, hydrodynamics, and plate tectonics. Aw yeah.))
Um, yeah. Sorry to use real science here, but...
The Moon's remains would still provide gravity, and loss of tides wouldn't be that bad. A few species would go extinct, but there's plenty of species not dependent on tides to replace them.
But badly made jokes aside, the mission is to conquer Earth. So Earth shall be glassed, mined, and destroyed. Then I will lie to myself and say they are the same thing. Or I'll roll a one and my death weapons will blow my shiny new fleet apart.
Support me instead, and mine the Moon