[tetron]

Yes, my recollection of the books is that it isn't about the need to keep consuming resources, it is about the premise that it is impossible to judge if another civilization is hostile or going to turn hostile

If your civilization can annihilated in a single strike, the only civilizations that survive have the strategy to a) avoid being detected and b) destroy anyone who has detected them (which results in destroying everyone, to eliminate uncertainty).

The idea being that assuming the actual survival of your species is at the top of your moral pyramid, all kinds of atrocities in its defense are justifiable.

[sliken]

Well it's all a side effect of nearly unlimited energy (I.e. enough to accelerate a mile wide asteroid up to nearly light speed) which cause asymmetry in warfare favoring offense. I'm sure humans would kill anyone outside their village/city if defense was impossible and anyone that wanted to kill your city/village just had to push a button.