The Trump administration waded even deeper into the Libya conflict this week, backing UN calls for a cease-fire amid the many factions, and signaling again that the country's oil fields are off limits to those seeking to profit on the war. The US initiative is well timed, with signs of an escalation of fighting between the Libyan Government of National Accord, which is recognized by the UN and backed by Turkey, and the insurgent forces of former general Khalifa Hifter, who has the support of Egypt, the United Arab Emirates, Russia and France. Libya's also become the world's most dangerous...