I assume your keys have been stolen. Probably by Otto von Bismarck? This is so "that which is seen, and that which is not seen" What about the opportunity costs, capital consumption, distruption, capital misallocation, and many more negatives of war/fight. In peacetime, entrepreneurs (and capital) are far more likely to focus on long term investments, research and development. It's capital accumulation which leads to longer more complex production structures (and innovation/inventions). And consumers will have more income and will look for new and improved products. Those are again incentives for entrepreneurs. I'm quite sure this is not exhausted list by far.