AP Photo

The attempt by Mr. Obama and his senior aides to fashion an extraordinary power-sharing arrangement between Mr. Maliki and Mr. Allawi never materialized. Neither did an agreement that would have kept a small American force in Iraq to train the Iraqi military and patrol the country’s skies. A plan to use American civilians to train the Iraqi police has been severely cut back. The result is an Iraq that is less stable domestically and less reliable internationally than the United States had envisioned.