If that's what you're worried about, the boomers may have been less irresponsible than previous generations, given the technology available to them. A few millennia ago, people were eradicating mammal species with stone tools.
Similarly: most species extinctions seem either to have occurred BCE or after the industrial era. The older extinctions caused by people who knew less about the impact of their (for instance) hunting, which makes them less morally culpable.
Also there is the important point that problems like environmental harm seem more acute now only because we are more aware of them. During the industrial revolution, the extent of the harm caused by the use of fossil fuels wasn't a consideration to anyone because we couldn't even conceive what it would mean. Ignorance is bliss.
Unfortunately, all of this is cold comfort when you have dark thoughts of widespread conflict over fresh water in your future.
[1] http://www.ted.com/talks/steven_pinker_on_the_myth_of_violen...
Then there was the entrenchment of the cult of the market into every corner of human thought, the sacrifice of compassion on the altar of misread darwinism and thermonuclear psychosis which now dictates every aspect of existence as a matter of presumed necessity. The deliberate development and adoption of a pseudomathematical framework to justify and rationalise absolute contempt for one's fellow man. Nothing short of the death of enlightenment ideals.
I freely admit that I cannot rigorously justify every aspect of my views in the manner that HN usually demands, but IMO pretty much anything that happened in the world during the period of time that the boomers had/have geopolitical, financial and cultural power is fair game to blame them for to some extent.
TBH I'm just trying to express how I feel when I think about my future and that of my friends. This probably isn't the best place for it, and so I'll leave it here before I say anything even more ill-thought-out.