By DAVID McHUGH, AP Business WriterFRANKFURT, Germany (AP) — For the second time, Israel has attacked Iran’s South Pars natural gas and its associated petrochemical complex – an energy lifeline for Iran that both helps keep the lights on for civilians and provides a key source of export earnings. Israel’s Defense Minister Israel Katz said Monday that Israel attacked a key petrochemical plant at Asaluyeh, the onshore industrial aspect of the gas field, which lies under the Persian Gulf. Katz said the “powerful strike” hit what he called “the largest petrochemical facility in Iran … responsible for about 50% of…