I've witnessed how one person who couldn't keep it together harmed a family two generations down the line. Life is hard and if you can give your kids a decent childhood, you've done your bit.
You don't have to do anything "globally". We're not pop culture superheroes out to save the world. The obsession with "making a dent"-porn has to stop.
If more people were "very nice on a personal level" we'd already be paradise.