Humanity is a type zero civilization and get all our energy from dead things, like trees, coal, oil and radioactive carbon/nuclear fuel, all of them deadly to all life on the planet. Burning poisons is not sustainable.
Anything that is not sustainable is TERMINAL.
Humanity is learning to move through the basic caveman types of passion, sectarianism, and fundamentalism A few threats consist of things like nuclear weapons, WMD, carbon global warming, and nuclear destruction. We have to evolve past all of these threats.
via Dr. Kaku; What Will It Take To Save Humanity And Join The Galactic Community As A Type One Civilization? ‘Civilized’ Humans Traveling On Earth Are Currently A Type Zero Civilization, Headed For Global Warming, Chaos, Then Extinction | A Green Road Journal