After the world wars we entered a time of global prosperity as a world. Globalism spread, technology increased productivity, shipping lanes were protected by the sole surviving super power, nearly everyone's standard of living increased, and our population had not yet exploded.
Since then we have depleted resources, added a few billion more people, and are now living an increasingly multi-superpower world. Declining resources per-capita and the visibility of richer persons via internet, etc, drives envy and in some cases necessity.
No one knows what the world looks like when it is not growing. No one alive has lived in a world that failed to grow. The world depends on so many pillars that are little more than ponzi schemes depending on perpetual growth. How the world will look when those pillars fail is anyones guess.
My guess is that increased nationalism, increased trade wars, increased protests is just foreshadowing of what is to come. Foreshadowing of the end of the global peace bubble.