Bottom Line Up Front: Through a series of unforced errors and myopic policy choices, the United States is abdicating its position as a global leader, leaving a vacuum that China and other powers vying for hegemony are eagerly filling.

Turkish intervention in Libya’s war stopped the besieged Tripoli government from collapsing. But fighting with Field Marshal Khalifa Haftar’s forces has since escalated, threatening a protracted conflict. Both Ankara and Haftar’s regional backers should urge their allies toward a return to negotiations and a ceasefire.

What’s new?* Middle East tensions spiked in the past year following attacks on oil tankers and Saudi oil facilities, the U.S. killing of a senior Iranian commander and Iranian military retaliation. Some of Washington’s allies, losing confidence the U.S. will reliably extend military protection, have started making cautious diplomatic overtures to …