Climate change activists around the world are protesting during the Global Week of Action; tensions between Iran, Saudi Arabia, and the United States continue to rise; and U.S. President Donald J. Tr…

The last major contest for the U.S. presidential nominations are held, Indian Prime Minister Narendra Modi addresses the U.S. Congress, and Switzerland votes on a basic universal income.

India's Prime Minister Narendra Modi visits Sri Lanka; the UN reviews its mission in Libya; and the fiftieth anniversary of the arrival of U.S. combat troops is marked in Vietnam.