I don't know the answer to these questions so in much of this I'm simply playing devil's advocate and asking questions.
On consumption: Sure it's not necessary. But it seems to be what we do. We base our growth, our success, nearly every measure on it, personal and otherwise. I don't like it, nor do I agree with it...but it is what we do. At least for now. Do people have the will to change it? Do people even see the need to? Dubious.
We burn oil and coal and waste energy without thought, then act surprised if it appears the military is being used to secure it. We love human rights the world over, African diamonds, cheap goods, and big profits on Wall Street. We love rainforests and dolphins and Indian tigers, but also like cheap canned tuna, warehouses full of copy paper, and vast soybean farms and cow feed lots.
It just seems that there is a major disconnect between people's noble intentions and criticisms and the way this civilization actually works. It seems to me that you cannot have all of this (the goods, the consumption, the energy use, the whole thing) without waging constant war on people, resources, animals, and the environment.
I suppose what really gets me in the end is the lack of acknowledgement and honesty about the levels of violence and exploitation (historically and right now) that are required to make all of this happen. It all comes at a cost.
On some level, don't really big appetites necessitate really big armies?