For weeks after the mass shooting at a gay nightclub in Orlando, Florida there were stories suggesting some alternative motivation, other than terrorism, for Omar Mateen’s actions. The most common was that Mateen was targeting gays because he himself was gay. One person, who claimed to be Mateen’s gay lover, said the attack was revenge because he believed he had been infected with HIV. Weeks later the FBI revealed that it had found no evidence to corroborate any of these stories. As far as they could determine, Mateen was not living a secret life.

So what did motivate Mateen? The obvious answer was a desire to commit a terrorist act. There was evidence to suggest he was a devout Muslim, but even so some in the media seemed eager to suggest the attack was just an unhinged man wrapping himself in a convenient pretext for violence.

The bulk of the evidence supporting the conclusion that Mateen was motivated by his support for ISIS wasn’t revealed until last week when Orlando authorities finally made Mateen’s phone conversations with police public in transcript form. From the Wall Street Journal:

“Yo, the airstrike that killed Abu Wahid a few weeks ago—That’s what triggered it, okay?” he told the police negotiator, an apparent reference in the transcript to the Islamic State commander.

Abu Wahib, whose real name is Shaker Wahib al-Fahdawi, was known as one of the group’s more Internet-savvy leaders, often appearing in propaganda videos.

Only an “avid consumer” of Islamic State propaganda would know when Abu Wahib was killed, said Seamus Hughes, the deputy director of George Washington University’s Program on Extremism.

“This isn’t somebody who decided that night he was going to wrap his personal grievances around ISIS,” Mr. Hughes said.

NY Times reporter Rukmini Callimachi, who covers ISIS for the paper, pointed out just how obscure the reference to Abu Wahib was on Twitter:

So Mateen’s attack was not that of someone who just wanted any available excuse for unleashing violence. He appears to have been a true believer. But the long delay in releasing this material, which allowed all the alternative theories to flourish, seems odd to the same reporter for the Times, as does the decision to quietly drop this on a Friday evening.

That’s certainly how it looks. It should not have taken months to get this material out to the public.