Each attempt will further deplete the spaceship and deny future generations a fighting chance, even when the time eventually arrives and the population sufficiently declines due to limits being reached.

Each (seemingly) successful attempt will enable those alive to thrive, breed and consume, further adding to the problems of (food and water) resource depletion and (air quality) global warming.

I don't believe these are as inevitable as you describe them.

We hear countless examples of how we can be affecting the ecosystem less harmfully or more helpfully, and this does not guarantee that we will then just populate to outstrip all resources. We've done that in this setup BECAUSE we had all this energy to do it with.

Examples of more positive interaction with nature.. Joel Salatin's 'Grass Farm' (see omnivore's dilemma), with multiple species of plants and animals deployed to support the grasses and treat the wastes of one as an input for another. Positive for healthy animals, foods, soils and groundwater. Labor intensive, but that's jobs.. Also, countless approaches to build and renovate homes for far better use of resources and energy, proximity to community, shops, work.

There are tons of efforts we can apply that do not add to the waste or resource depletion, provide meaningful work and more meaningful lifestyles (regaining consciousness after the Video slumber of the last 50 years..)

For me, the 'Greatest Good' gets into parsing out the materials, habits and energies in our lifestyles, and bit by bit learning to 'Do No (Do Less..) Harm'. There are so many ways to work WITH the energies and materials around us without wasting them away. Population, I'm guessing, will simply mirror the available energy supply.. it has no choice. It will go down, maybe way down.. but not away. But we, in the meantime, have lots of other choices we can be making.

I just spent the afternoon blowing cellulose insulation (recycled newspaper, it seems) into the 160year old plaster walls in one more room of my house, using a homemade blower built from a few recycled plywood Political Roadsigns, some tubing and PVC pipe and a surplus blower motor. Works Great, More Filling! I can't wait to rent it out to my neighbors, or trade it for Pie and Piano Lessons! (One kid, and it's gonna stay that way)

Bob