Does the earth have enough resources for all countries to have the similar levels of affluence as we have in Canada and the US? Not. A. Chance.
Sure, we all say - well, most of us anyway - that we'd like everyone on the planet to live as comfortably as us, but that would be impossible. For everyone on the planet to have a decent roof over their head, three square meals a day, sufficient clothing, a few mod cons, etc. - you know, the basics - it will mean facing the elephant in the room. It would mean that we have to make sacrifices. Real ones, such as: eating meat maybe 2-3 time a week, mass adoption of public transit, having no more than one vehicle, massive curtailment of international travel, no more McMansions.
Sorting our waste and recycling? That's barely picking around the edges of what's required and people b!tch about that. Carbo taxes? People here are losing the minds over them. So, I don't know what appetite we - as a society - will have for making genuine efforts to make this planet livable for the rest of humanity right now, never mind future generations.