Iranian-backed Shia militias pose a growing threat to Israel from Syria and Lebanon. Photo: Iranian government media. Iran “exerts near-complete control” over a network of tens of thousands of close allied fighters across the Middle East and has ties to tens of thousands more, posing the Islamic Republic’s most formidable challenge to the US, according to a new a research report by non-profit think tank the Rand Corporation. The report describes that the so-called Iran Threat Network (ITN) — a force of tens of thousands of fighters from non-Iranian, non-state proxy and other groups, in places including Syria, Yemen, Iraq and the Palestinian Territories — has become a much larger and more mobile network, and will continue to threaten US interests.