Along the 220-kilometer (137-mile) main road from Karbala to the border with Saudi Arabia there is a vast open desert that also extends to Syria and Jordan. While some of the checkpoints on the road are manned by the Iraqi army or police, most are controlled by a Popular Mobilization Units (PMU) group known as the Al-Abbas Combat Division. The organization is funded and politically backed by the custodian of the shrine of Imam Al-Abbas, Sayyed Ahmed al-Safi, Grand Ayatollah Ali Sistani’s representative in Karbala.

Every few kilometers, the flag of the group could be seen at a checkpoint, along with a group of fighters with military-style clothing. Sajjad, a fighter at the al-Nukhaib crossroad, 120 kilometers (75 miles) from the Saudi border, said he had chosen to fight and sacrifice his life for Al-Abbas ibn Ali, who was killed in the Battle of Karbala in 680. Al-Abbas ibn Ali was the son of Shiite Islam's first imam, Ali ibn Abi Talib. Sajjad said his commitment to the Al-Abbas Combat Division is a commitment to the maraji, the senior Shiite clergy headed by Sistani. The fighter indicated that he wanted to fight for Iraq, and that with this faction he is not linked to any outside, foreign agenda.

It is rare for a PMU group not to have links with Iran, and this makes the Al-Abbas Combat Division one of few exceptions within the PMU, which reports directly to the Iraqi prime minister.

“We were normal people who decided to fight to preserve their dignity after Daesh (the Islamic State) took wide areas of Iraq,” said Abu Ali, a field commander. Abu Ali said the Al-Abbas Combat Division and the Imam Ali Brigade, whose main operations are in Najaf, were the first to respond to the call to battle the Islamic State in 2014 by Sistani, who is based in Najaf. Abu Ali said, “One of Daesh's main goals was to enter Karbala and Najaf and destroy the shrines to humiliate our people; we left everything and took to the fronts to prevent this from happening.”