Iran’s move to suspend cooperation with the 2015 nuclear deal threatens to further escalate already high tensions between Washington and Tehran.

Tensions over Israeli treatment of Palestinians in Jerusalem have spurred the worst violence between the two sides in years, but the eruption seems unlikely to prompt a strong international reaction…

U.S.-Russia bilateral relations have fallen to a new low, with Ukraine, Belarus, cyberattacks, and nuclear weapons among the biggest disagreements. What’s the best way to judge this summit’s success?…