Given that is so, what help and encouragement do those that remain need from those whose work is done? Moses reminds Joshua, "You have seen with your own eyes all that the Lord your God has done to these two kings. The Lord will do the same to all the kingdoms over there where you are going. Do not be afraid of them; the Lord your God himself will fight for you" (Deut 3:21f). And the LORD's instructions to Moses are to "commission Joshua, and encourage and strengthen him" (Deut. 3:28).
Joshua is to draw strength and hope from the Lord's previous dealings with his people and is to proceed with courage, trusting in the Lord. It is all so very general, so imprecise, so indistinct. But maybe precisely and distinctly so. Joshua does not need a detailed strategy; he needs a vision of hope. He doesn't need tactical insight but strength and resolve. There will be time enough for the Lord to direct him in detailed terms for the work he calls Joshua to do; for now, he needs what the LORD and Moses offer him.