PMU Iraq
The following American PBS TV report aired in December 2017. It explains exactly who the Popular Mobilization Units (PMU) of Iraq are.

The group's Iraqi-Iranian deputy leader, Abu Mahdi al-Muhandis, was the other high-profile commander the US assassinated alongside Iranian general Qassem Soleimani at Baghdad Airport last week.

In this report, you'll learn that the PMU did almost all the actual fighting and dying to prevent Baghdad falling to ISIS in 2014-15. Without them, Iraq today would literally be 'Islamic State'.

PMU officers acknowledge that without Iranian support - which is primarily supplied to them in the form of advisors - they could not have succeeded in defending Iraq. Otherwise, the PMU are staffed by IRAQI patriots.

These are the 'terrorists' - engaged against ISIS near the Syrian border - who the US bombed on December 29th, killing 25 of them. These are the 'terrorists' who then protested the US assault by barricading the entrance to the US embassy in Baghdad (killing no one)...