Superpowers cannot solve world’s problems, UN chief says in final general assembly address

António Guterres says humanity faces unprecedented convergence of threats but mechanisms for collective action are under growing strain The world’s fault lines have turned from cracks into canyons as superpowers show that they alone do not have the military, economic and technological power to guarantee security or solve the world’s problems, the outgoing secretary general of the United Nations has said in his final address to the general assembly.

In a speech laced with despair but also glimpses of defiant hope, António Guterres said that over the last decade, largely spanning…