This strikes me as flamebait but I'll try to answer it anyway - apologies if I'm wrong about your intent.
Intent is a consideration. Undoubtedly war has driven a huge number of advances for mankind that have eventually helped to make life better - medicine, explosives (I'm thinking construction here, not destruction). Even the Space Program got a boost from war - from Congreve's rockets to the German V2 program.
But whether the good derived from those secondary and tertiary benefits outweighs the evil of war is a question for God, not me. I do believe that the benefits derived from space exploration more than outweigh the costs involved. And the intent of exploration is usually benign at worst where the intent of war is usually malign.