The North Atlantic Council Monday nominated French Air Force Gen. Denis Mercier to the post of Supreme Allied Commander Transformation (SACT), headquartered in Norfolk, Va.Mercier will succeed French Air Force Gen. Jean-Paul Palomeros at a change of command ceremony in September in Norfolk.Mercier will be the third French Air Force chief of staff to command SACT. Before Palomeros, in 2009, French Gen. Stephane Abrial became the first non-U.S. officer to lead the command, becoming one of NATO's two supreme allied…