The Gulf nation’s ground troops have cultivated alliances in Yemen with local armed groups, but its ability to shape the civil war’s outcome is limited.

Saudi Arabia pressed Lebanese Prime Minister Saad Hariri to resign to try to weaken Iran-backed Hezbollah in Lebanon. The path to resolving the crisis could run through Yemen.

Iran could restart aspects of its nuclear program if President Trump declines to renew sanctions waivers this month, leaving major powers with few options for monitoring or restricting it.

Averting famine will require Saudi Arabia to permit the resumption of commercial shipping of food and fuel to the besieged country.

Military threats to deter chemical attacks have so far failed to restrain the Syrian regime, and they risk escalating the horrific conflict even further.

President Trump’s denunciation of the Iran nuclear deal has put the agreement on shaky footing, even if Congress declines to reinstate sanctions.

Spain’s effort to block Catalonia’s referendum on independence may push more Catalan voters to support it.