BEIRUT — With the World Cup in faraway Brazil coming at a time of unprecedented sectarian violence and soaring tension in the Middle East, some Arab football fans have been reduced to watching matches in secret or even — and this is where it gets complicated — on a TV channel owned by Israel. Since the World Cup kicked off three weeks ago, Sunni Muslim extremists have seized territory in Iraq and Syria and declared an Islamic state. Lebanon has been hit by a spate of suicide bombings. Israelis and Palestinians were pushed on the edge of full conflict after the murders of four teenagers. Egypt’s political divide grew wider as hundreds of people charged with supporting the ousted Muslim Brotherhood group were convicted of terrorism-related crimes — including three journalists for Qatar-owned Al-Jazeera network. Many accuse the Doha-based network of editorial bias in favor of the now banned Islamic group in Egypt and of Sunni insurgents fighting Shiite-dominated governments in Syria and Iraq. Qatar’s media conglomerate owns broadcasting rights to the World Cup in the Middle East, charging viewers from $110 to $320 for a three-month subscription that includes the 64 World Cup matches — a tournament that should…