“Once upon a time climate change was a strictly environment and development issue. Today it has become a matter of national and international security. Efforts to link climate change with violent conflict may not be based on solid evidence, but they have certainly captured the attention of governments,” says the International Institute for Environment and Development.
From the IIED commentary:
The truth is that there are, as yet, no concrete examples of violent conflicts induced by climate change, and a limited understanding of what the future holds. Take the example of water wars: many researchers argue that it is not climate change that is to blame, but rather it is issues such as poor governance of water resources that are the driving factor behind such conflicts.
BTW, the IIED advocates adaptation to climate change as opposed to the shutting down of the global economy.