The countries are "discontent". Russia "resents". Iran has attacked US bases. This is the level of this article. Nowhere any mention of aggressive actions taken by the US.
Millions upon millions of disenfranchised young people with no where to go. Before 2019 those millions at least had the hope of moving to one of the still wealthier countries, which alleviated some of the pressure and anger back home. Now that pathway is increasingly more difficult and harder to justify, plus the people in the wealthier countries themselves are starting to feel the same anger and pressure, but have nowhere else to go.
All that pressure and anger will need to be directed somewhere, and I'm sure the leaders of such countries would prefer it goes outward than inward.