Does water cause conflicts or not?

British author Wendy Barnaby earlier this year wrote a piece in Nature magazine questioning whether the popular premise (discussed many places including here on this blog) that water scarcity will inevitably lead to conflict actually is right.

See: Do Nations go to War Over Water? (subscription)
Nature 458, 282-283 (19 March 2009) | doi:10.1038/458282a; Published online 18 March 2009
http://www.nature.com/nature/journal/v458/n7236/full/458282a.html

(for a preview, see Slate: http://www.slate.com/id/2215263/ )

We had posted an article last November citing to the International Crisis Group's findings that scarcity may actually lead to increased collaboration among nations that would otherwise compete for shared resources:

International Crisis Group recently released a report on Climate Change and Conflict which read in part:

"Importantly, climate and environmental stress may also play a role in producing collaboration instead of violence. Water is an important example. Historically, water scarcity has often – though certainly not always – worked to favour cooperation between states. Interstate dialogue prompted by diminished water supplies, particularly, can build trust, institutionalise cooperation on a broader range of issues and create common regional identities."
see: http://www.crisisgroup.org/home/index.cfm?id=4932

Despite Ms. Barnaby's analysis, conventional wisdom still sounds the alarm on "water wars" - see (or hear!) for example, a recent piece by NPR on water shortages in Iraq and potential conflict with neighboring Turkey which controls the headwaters for most of Iraq's river water.
http://www.npr.org/templates/story/story.php?storyId=112494850