some green thinkers are now coming to a surprising conclusion: In exceptional circumstances, they say, the only effective way to protect the environment may be at the barrel of a gun. [...] in certain cases of severe ecological harm, the international community may be justified in mustering troops to intervene, with or without the permission of the host country. [...] "If you consider how people fight over oil and other resources, I don't see any more noble cause than to fight over the preservation of the planet," says Alex Cornelissen, director of Sea Shepherd's Operation Galapagos.
In South Africa, a college for rangers, established about 20 years ago, offers military-style training to park rangers from around the continent. In recent years the urgency has grown. Many contemporary poachers form heavily armed, well-organized gangs, often from neighboring countries. [...] According to estimates, about 1,000 rangers worldwide have been killed in the line of duty in the past 10 years, 130 of them in just one national park, Virunga, in the Democratic Republic of Congo. [...] After taking office last May, Brazil's new environment minister, Carlos Minc, sent the military to seize cattle on illegally deforested land, and he has suggested that army regiments patrol the Amazon's nature reserves.
possible scenarios in which armed intervention might be called for on ecological grounds [...includes...] an imminent environmental disaster [...] in which spillover effects to neighboring countries were foreseen [...] would be consistent with existing international law, because the goals would include protecting citizens from the repercussions.