Sheltering from air raid sirens in Kyiv last month, Ukrainian meteorologist Svitlana Krakovska said what we all know: climate change and the war on Ukraine are both rooted in fossil fuels, and our dependence on them. This conflict is hastening a difficult but crucial transition for Germany. In recent years, it has made significant strides in recognizing climate's links with national security. This alone has not freed the country from the tether of Russian oil and gas. The shocking force of Russia's invasion, financed by its grip on the world fossil fuel market, shows that Germany's national security depends on...