With another extension of the U.N.-sponsored cease-fire, Yemen's civil war could be edging toward a frozen conflict, reducing the likelihood of Houthi attacks on Saudi Arabia and the United Arab Emirates. On June 2, the U.N. special envoy for Yemen said the Saudi-backed Yemeni government and Houthi rebels had agreed to extend their latest cease-fire under its current parameters for another two months. The truce -- which began on April 2 and is now set to expire on Aug. 1 -- marks the longest-lasting national cease-fire that Yemen has seen in six years. The agreement includes allowing humanitarian aid and fuel through al-Hudaydah, some flights into Sanaa airport and talks to reopen roads about besieged Taiz....