The link between ecology and war

You might remember a discussion about betting on Democracy for Oil some time ago. Here is a piece in Haaretz (a leading Daily from Israel) that attepts to talk about the link between ecology and war:

In the 1970s, the environmental discourse was focused on the dwindling natural resources of the entire planet as a single unit. Now the discourse is about how those resources are divided up among the countries and inside them. When the wealthy industrialized nations organize their global security concepts to guarantee free access to energy sources, and when their overuse of those resources accelerates the pace of global warming, an absurd situation results: Armies go out to occupy or safeguard oil reserves, while unbridled exploitation of those reserves could even threaten the victors.

I find that a fairly good assessment. Energy and Water will be the resources over which wars may be fought in this century. Do they have to be fought?