I am not sure that climate change has to encourage war-driven destruction processes. Most likely, war is not the way to overcome a climate or geological change. It is commonly assumed that wars are waged for resources. But excuse me, were the World War I or the Vietnam War, or even the World War II or the current Iraq War, fought for resources?! I have a difficulty to find examples of wars genuinely and actually fought for resources. Is there a point to wage a war for resources that costs the same ammount of resources? Wars might be a luxury of the past, not a necessity of the future.
The main "technology" of overcoming a tough climate change could be ethical after all. Of course, this does not mean that people would not do stupid things. We might indeed talk ourselves into the acceptance of wars as the most normal solution to survival problems. But that would be very immature of us. On a cosmic scale, the civilisations that go beyond their birth planets are probably those without the "natural" assumption that when two civilisations meet, something must turn to dust and stone. There is enough dust and stone across the universe, isn't it?