The Battle Front?
The so-called 'libertarian' groups are at the forefront in maintaining the expansionist economic paradigm, which is driving our planet's unsustainability. How do they ignore the ecological realities which face our planet?
The Cato Institute frequently publishes 'papers' by Randal O'Toole - the self proclaimed AntiPlanner - http://ti.org/antiplanner/
O'toole also leads a little group that has suburb and car adulation rallies once a year - http://americandreamcoalition.org/index.html
Where is the consideration of ecological realities? Do they have any proof that global consumption of resources has decreased over the years. Not likely, but these groups prefer to cherry pick by using minor details and ignore the larger realities of the situation. The libertarians and antiplanners love to focus on predictions made about the depletion of individual resources. But, for example, the fact that Ehrlich's predictions were off, does not prove anything, except that Ehrilch may not in fact be a fortune teller.
Either way you cut it, we are depleting our natural capital and at some point in the not too distant future we will face serious ecological collapse, at which point the ecological economists will be irrefutably vindicated, but it will be a little too late.