Yemen has received three UN envoys since 2011. They proposed various suggestions and ideas to help the warring sides come closer and narrow the disparities. However, the adversaries relentlessly stick to their demands, rendering all UN-sponsored peace efforts fruitless.

On June 15, the outgoing UN envoy to Yemen Martin Griffiths lamented that the parties to the conflict have not yet overcome their differences. No one envisioned that Griffiths would wind up like his two predecessors, Jamal Benomar, who quit in 2015 after four years in the post, and Ismail Ould Cheikh Ahmed, who resigned in 2018. Three UN envoys over 10 years worked to dismantle the engine of tensions and war but to no avail. This is not due to the incompetence of the mediators. Instead, it is a projection of the extreme intricacy of the conflict in Yemen.

Washington has also gotten involved in efforts to end the war. In early February, the Biden administration — in one of its first major foreign policy initiatives — appointed US diplomat Timothy Lenderking as special envoy to Yemen. In remarks announcing the appointment Feb. 4, Biden said the administration was "stepping up diplomacy to end the war in Yemen — a war which has created a humanitarian and strategic catastrophe."

"Yemen is a tale of missed and lost opportunities. I've learned in a lifetime of involvement in conflicts that the opportunities are often there but the courage needed to take them is rare," said Griffiths in his final briefing to the UN Security Council.