What do we know about Orlando killer Omar Mateen?

In the wake of the deplorable mass shooting at an Orlando nightclub on Saturday - and the deranged shooter’s tenuous connection to Isis – “national security” is about to take on a renewed focus in the presidential race. But the existential threat to Americans is not some fanatical and nihilistic death cult halfway around the world: it’s the fact that unstable individuals of all stripes continue to have easy access to assault weapons right here in the US.

While no one is doubting the Orlando mass murderer called 911 and pledged allegiance to Isis before continuing his senseless killing spree, the facts are much more complicated than that. Even US officials admitted: “there was no indication that [Isis] had trained or instructed him, or had any direct connection with him”. As one senior US official put it to the Wall Street Journal said on Sunday: “He seems to be looking for any opportunity to associate with the terrorist group du jour.” Isis quickly took advantage of the tragedy to take credit, but “they may just be piling on”, a senior US official said.

Much more evidence points to the idea that he was unstable before Isis came into existence. He was reportedly a domestic abuser, according to his ex-wife, who said she thought he was mentally ill and not devoutly religious. His co-worker quit his job more than a year ago because “everything he said was toxic”. “This guy was unhinged and unstable,” the co-worker said, “he talked of killing people”. His father said that the crime did not have anything to do with his religion and was because he was offended seeing two men kissing weeks earlier.

When the killer in these types of mass shootings is white, as the vast majority of them are, Republicans are happy to discount their extreme conservative political views as the ravings of a madman. Yet when a probably unstable American shouts “Isis”, that discussion halts and it’s immediately considered an act of war.

Really, mass shootings have always been a form of “terrorism”, we just don’t call it that because the perpetrators do not usually have a Muslim-sounding name. No matter the particularly hateful motive – whether its purported support for a terrorist organization, hatred of gay people, racism or a fanatical hostility towards abortion rights – there’s one thread that connects many of these shootings: easy access to guns that facilitate killing lots of people at once.

We now know that almost all of the well-known mass shootings in the past several years – whether it was San Bernardino, the Newtown school or the Aurora movie theater – have featured one particular weapon: the AR-15, which can shoot a large quantity of ammo in short bursts. As the Washington Post noted, they have become the mass shooter’s weapon of choice: “There have been eight high-profile public mass shootings since July of last year, according to a database compiled by Mother Jones magazine. Assault-style rifles were used in seven of those.”

FiveThirtyEight detailed on Sunday that since 9/11 over 85% of terrorist attacks have involved guns. And as the president himself has correctly pointed out, mass shootings with no “terrorism” motive also dwarfs the number of shootings involving members of a foreign terrorist organization by orders of magnitude.

But you can count on Republicans (and some Democrats) to once again use this tragedy to push for expansive new surveillance laws instead of focusing on the instruments that have actually killed all those people. But based on early reports, this was not a situation where more spying would have helped: Mateen was a known quantity to the FBI, having been investigated twice, and the cases were dropped for lack of hard evidence.

The FBI’s investigations and decision to close them will certainly be dissected over the coming days, but the Guardian’s Spencer Ackerman made an important and overlooked point on Sunday: “Consider implications of keeping everyone interviewed by FBI under suspicion indefinitely, after FBI closes inquiries.” Even counter-terrorism officials admit the “profound” privacy risks if the FBI starts spreading around information on closed case files to other agencies.

Lone wolf attacks are notoriously hard – and in many cases impossible – to stop, no matter what invasive laws are in place. If you have an unstable individual who is set upon destruction, doesn’t tell anyone and is willing to die, there is often little recourse for law enforcement. Tragedies like these will, sooner or later, inevitably result.

As long as instruments of mass death are widely available in our country, we will continue to see many more mass shootings that kill dozens of people than the rest of the western world. It’s that simple.