Former Army psychologist Nidal Hasan, the perpetrator of the 2009 Fort Hood shooting that killed 13 and injured dozens, has written a letter from prison to ISIS caliph Abu Bakr al-Baghdadi requesting citizenship in the Islamic state.

"I formally and humbly request to be made a citizen of the Islamic State," Hasan wrote in the letter, according to Fox News. "It would be an honor for any believers to be an obedient citizen soldier to a people and its leader who don't compromise the religion of All-Mighty Allah to get along with the disbelievers."

Hasan currently resides in the military's death row in Fort Leavenworth, Kansas. He was sentenced to death for the shooting in August 2013. Despite Hasan's stated motivations for the attack, his history of jihadist sympathies, and the fact that he shouted "Allahu Akbar" (God is great) before opening fire, the U.S. has refused to call the shooting an act of terrorism, and instead refers to the event as an act of "workplace violence."

It's clear that Hasan's jihadist sympathies for ISIS have reached a new level. Perhaps now the U.S. will reclassify the Fort Hood attack as what it truly was: an act of terrorism against American soldiers.