Marrying asteroid defense and asteroid mining

I would place it in the L5 moon-earth LaGrange point for mining, processing,
and construction if I moved one. Otherwise it's stuff processed and made at
the asteroid site and all you can carry to the L5 point and stockpiling,
processing, and more construction there, as well as shipping materials and
finished products to earth, some directly and some from L5. But we can
build the vehicles we need at the asteroid too, installing, at first, needed
light weight components launched from earth. Later we make most everything
ourselves, of course.