Perhaps not very optimistic but: 1. Climate change is ignored by the US and China (who combined make up half of emissions). It snowballs until it becomes irrev

Perhaps not very optimistic but: 1. Climate change is ignored by the US and China (who combined make up half of emissions). It snowballs until it becomes irreversible and catastrophic. 2. Countries lurch from natural disaster to natural disaster, incapable of focusing on more than short-term aid for its panicked citizens. 3. Large groups of people become climate refugees as their towns/cities become uninhabitable from flooding, fires, disease, etc. Some desperately try to get entry into 1st world countries. 4. Amongst xenophobia and desperation to do something about seemingly endless natural disasters, we see a rise of countries lead by strong dictator-types, who promise that they will fix our problems where others have failed. 5. Hard clamp down on immigration. Human rights violations, genocide, world war. 6. Still no level 4/5 autonomous vehicles.