Well, I did say 'refining' in addition to manufacturing. In some cases refined raw material makes sense to deorbit. But if you consider the costs of lifting obj

Well, I did say 'refining' in addition to manufacturing. In some cases refined raw material makes sense to deorbit. But if you consider the costs of lifting objects to orbit, the ability to manufacture large mass components in orbit would be a huge win. Sure, the initial costs of getting to the point where you can manufacture in orbit are large. But, if space mining becomes profitable they'll need more and more gear to do this. If they have to lift all that gear off earth then it is prohibitive. Hence space manufacturing is a self-help path for mining.