All this "Save the earth" projects or themes won't make sense if a random asteroid came from nowhere and hit our planet, wiping out everyone. I think our priorities are misplaced. We should be looking at saving each other, avoid pointless wars and survive peacefully.
You're right to an extent, we can save the world by living a peaceful life together with our brothers, neighbors and everyone at large, most problems encountered today were as a result of our individual differences that stirs up conflict amd we should count it a privilege not being struct by a natural epidemic that could cause a massive loss of lives, also we must be conscious of the environment we leave in to make it a better place for a living and the activities we do on it determine the reactions we get from the nature itself either good or bad.