90% is an interesting figure, since that seems to have been the die-off rate among American Indians, Pacific Islanders, etc when Westerners came on the scene. It's not just a figure pulled out of a hat either, it shows up everywhere, for instance search "peak oil" on google video or youtube and you'll find an interesting movie about some of the lesser-visited Pacific islands and there are figures like, 6000 people used to live on this island, now there are 600.

Now we Westerners get to enjoy what we have imposed on others.

And yes, the other guy is NOT dumb. The American/Iraqi kill rate has been something like 50:1 in this latest war, but that's because we have all this neat hardware and gas etc to run it on. On an equal footing, if someone were to wave a magic wand and eliminate humvees and helicopters etc. they'd kick our asses. When we're ALL scrawny and hungry and canny from years of survival, who knows, after all we European-extraction types have been through as harsh a winnowing process over the centuries as anyone, and the ways we've treated each other through centuries of wars and famines etc make most indigineous groups look like lapdogs.

The other guy is definately not dumb though. Soldiers in Vietnam were amazed at the intelligence, resourcefulness, and creativity of the Vietnamese, whether it was in their farming technology, fish traps, or soldier traps. The Polynesians have cultures that emphasize being the brutal badass but their crafts show that the only reason these guys didn't come up with something like the Space Shuttle is they lacked the fuel etc lol.

If there's one major leap forward for us Western cannibals over the last 100 years, I'd have to say that 100 years ago we had utter contempt for anyone who wasn't a workaholic, pleasure-denying, type A person. We're the ones who justified genocide against the Indians because we saw them as lazy and hedonistic, and therefore "animals". This attitude is still prevelent, but now it's not absolute. There are a lot of us realizing our Westerna culture involves working perpetually harder for less, and killing the Earth in the process.