After initial reports of multiple snipers in the Dallas massacre on Thursday night, it became apparent that the mass murderer was one man — a former soldier named Micah Xavier Johnson. How did a decorated Afghanistan combat veteran end up among the worst of police assassins in US history? CBS News dug into Johnson’s background, and found a disturbing decline in his behavior, but nothing that would have warned law enforcement of the imminent threat:

This video report has less information than the accompanying article. As it turns out, the Army booted him out of Afghanistan for serious misconduct — serious enough to recommend a disciplinary discharge rather than counseling:

Starting in 2009, Johnson served in the Army Reserve as a private first class with a specialty in carpentry and masonry, the military said. In May 2014, six months into his Afghanistan tour, he was accused of sexual harassment by a female soldier. The Army sent him stateside, recommending an “other than honorable discharge,” said Bradford Glendening, the military lawyer who represented him. That recommendation was “highly unusual,” Bradford said, since counseling is usually ordered before more drastic steps are taken. “In his case, it was apparently so egregious, it was not just the act itself,” Glendening told The Associated Press. “I’m sure that this guy was the black sheep of his unit.”

And that’s his attorney speaking. The victim felt compelled to get a protective order, which a judge granted. His attorney expected Johnson to get the ignominious boot, but was surprised when the Army granted him an honorable discharge instead. To this day, Glendening doesn’t understand how that happened.

Johnson stewed afterward about his treatment, becoming more and more radicalized, but without taking any action. That changed this week after the two separate incidents in Baton Rouge and Saint Paul, but Johnson may have been egged on by radical organizations with whom Johnson connected on Facebook. Those included the New Black Panther Party, as well as two others less well known:

But one of the groups Johnson “liked” on Facebook, the African American Defense League, posted a message earlier in the week encouraging violence against police in response to the killing in Louisiana. “The Pig has shot and killed Alton Sterling in Baton Rouge, Louisiana! You and I know what we must do and I don’t mean marching, making a lot of noise, or attending conventions. We must ‘Rally The Troops!’ It is time to visit Louisiana and hold a barbeque.” The message was attributed to Dr. Mauricelm-Lei Millere, a leader in the organization. Another group Johnson “liked” was the New Black Panther Party, whose leaders have “long expressed virulently anti-white and anti-Semitic opinions,” according to the Southern Poverty Law Center. Johnson also “liked” the Nation of Islam and the Black Riders Liberation Party, which the center described as “hate groups.”

Sounds like quite the charmer indeed. None of those groups will bear any legal responsibility for the shootings — the Brandenburg case applies here — but they certainly have a moral responsibility for stoking these tensions. In the end, though, Johnson bears the full responsibility for his crimes, although if media treatment of the Tea Party, NRA, and pro-life groups were consistently applied here, we should see lots and lots of group blame from the media laid on Black Lives Matter protesters. It wouldn’t be right, but at least it would be consistent.

Had the Army followed through on its initial plan to issue a dishonorable discharge through a court-martial, there’s a chance this could have been prevented. Such a discharge amounts to a felony on one’s record, which would have made Johnson ineligible to purchase firearms. I suspect, however, that Johnson would have been motivated to get his hands on a weapon to carry out this plan through other channels. The firearm wasn’t the problem here — it was the shooter.