From the blog called Living On the Real World: Climate resilience comes to the Pentagon. An excerpt:

The “challenge of global climate change, while not new to history, is new to the modern world,” Hagel told the Halifax International Security Forum. “Climate change does not directly cause conflict, but it can significantly add to the challenges of global instability, hunger, poverty, and conflict. Food and water shortages, pandemic disease, disputes over refugees and resources, more severe natural disasters – all place additional burdens on economies, societies, and institutions around the world.”