The top U.S. general told lawmakers on September 22 that he does not believe it would be wise to share intelligence with Russia in Syria should Washington and Moscow work together to fight Islamist extremists in the war-torn country.General Joseph Dunford, chairman of the Joint Chiefs of Staff, made the remarks in testimony before the Senate Armed Services Committee on the same day that the United States and Russia failed to reach an agreement on salvaging a shattered cease-fire in Syria.