According to historian Jared Diamond, we currently have four global crises to address: the ongoing threat of nuclear attacks, climate change, running out of resources, and socioeconomic inequality.
Diamond believes there's hope for the future, though, because these problems are human caused, and must have human solutions - they are not looming doomsdays like an asteroid poised to strike Earth (of which we are currently largely helpless to address).
If we don't aim to solve these issues within the next 30 years, then we - and our children - may end up living in a "miserable world not worth living