A former C.I.A. officer calls Suleimani, the head of Iran’s Quds Force, the “most powerful operative in the Middle East today.”Illustration by Krzysztof Domaradzki Last February, some of Iran’s most influential leaders gathered at the Amir al-Momenin Mosque, in northeast Tehran, inside a gated community reserved for officers of the Revolutionary Guard. They had come to pay their last respects to a