These PMU troops are not yet part of the Iraqi army. They are volunteers but they are financed by Iran. The US has been bombing them for years. They have also been bombing the Syrian army to protect Al Qaeda and ISIS. The US is protecting the Kurds who are invading Syria to benefit their Israeli allies. The US has dropped leaflets warning the Iraqi army to stay away from Kurdish areas in Syria. The Kurds have persecuted Arabs and even burned down their houses to convince them to leave their homes. At present the Pro-Iranian PMU forces are near the Iraqi Syrian border. Their allies the Syrian army are not far away. If the Russians decide to defend the Syrians and the Iraqis, there will not be much we can do. The Russians have superior air power and ECW. Look up Khibiny.