Among the treasure trove of documents released by U.S. authorities May 20 detailing terrorist leader Osama bin Laden's life and aspirations are some morsels throwing further light on his rift with Al-Qaeda's affiliate in Iraq.
The documents, which were swept up from bin Laden's compound in Abbottabad, Pakistan the night he was killed by U.S. Navy Seals in 2011, also reveal bin Laden attempted to reunite with his estranged son, who was under house arrest in Iran.
Little was known while bin Laden was alive about his disagreement with the tactics employed by Al-Qaeda in Iraq -- the group that would later morph into the Islamic State -- although he was known to take issue with the Iraq group's killing of Muslims along with infidels in suicide attacks.
But before the Iraq affiliate was nearly exterminated by U.S. troops in May 2007, the documents reveal bin Laden received a letter from "the Jihad and Reform Front" imploring him to disavow "the ongoing catastrophes and disasters" being committed by the Iraq group.
"If you still can, then this is your last chance to remedy the Jihad breakdown that is about to take place in Iraq," the letter warns bin Laden.
Bin Laden did reject the splinter group, but it managed to survive and eventually morphed into the Islamic State, which after bin Laden's death went on to seize a swath of Syria and Iraq, killing Muslims and Christians alike and publicly beheading Westerners.
IS has since declared a "caliphate" in the lands it conquered -- something bin Laden warned would be premature in light of the ongoing jihadist struggle against the West.
As his influence and success waned, the documents show bin Laden expressed disappointment in several failed attacks, including in Russia, Britain and Denmark, attributing them to "bad luck and God wasn't on our side."
But in a touching note that gave a rare glimpse of the human, domestic side of bin Laden, the documents revealed that just one month before he died, his aides tried to reunite him with a beloved son, Hamza, who was under house arrest in Iran.
In a message dated April 2011, an Al-Qaeda operative named "Mahmud" wrote to bin Laden describing efforts he was making to smuggle his son, who he described as "very sweet and good," to meet with him.
"I have tried to find a way to send him to you on the main road, but I was not able to find one due to the intensified security procedures and searches," Mahmud wrote.
Hamza and other family members, including his mother Khairiyah, bin Laden's third wife, spent years in Iran, where they fled after the Sept. 11, 2001 terrorist attacks.
In a message to his father dated July 2009, Hamza lamented that he "was separated from you when I was a small child, not yet 13. ... You might not recognize me when you meet me, as my features have changed."
"But what truly makes me sad," Hamza added, "is the Mujahidin legions have marched and I have not joined them."
U.S. officials said it was unclear if Hamza bin Laden ever got a chance to see his father before the U.S. raid. A U.S. official said he did not know where Hamza is today, or if he even is still alive.