BAGHDAD (AP) — The new patriarch of one of the most important Christian churches in the Middle East assumed his duties Friday in the Iraqi capital weeks after he was elected for the post. Polis III Nona, who was born Amel Shamoon Nona, 58, replaced Cardinal Louis Sako of the Chaldean Catholic Church, who stepped down in March saying he had asked to retire to pursue “prayer, writing and simple service.” The new patriarch previously served as the Archbishop of the northern Iraqi city of Mosul and the Archbishop of Sydney, before becoming the patriarch for the Chaldean Catholic Church in Iraq and the World. He was elected on April 12, a month after Sako, 76, retired. Partriach Nona’s inauguration comes at a time when the numbers of Christians in Iraq have been dropping since the 2003 U.S.-led invasion that toppled Saddam Hussein and the rise of the Islamic State group before they were defeated.…