NBC News reported this morning, "How does a man investigated by the FBI for possible links to terrorism buy an assault-style weapon in America? Easily."
In the case of Omar Mateen, the apparent gunman in the worst mass shooting in American history, the Floridian legally bought an AR-15-style weapon and a semiautomatic pistol recently, despite the fact that the FBI was aware of him and looked into him twice.
It was not immediately clear what if any watch list [the apparent shooter] was on at the time of the Orlando massacre -- though he had come across the FBI's radar on more than one occasion. He first came to the FBI's attention in 2013 after co-workers reported he'd made "inflammatory" comments to them about radical Islamic propaganda. A year later the FBI looked into him again because of his ties to an American who traveled to the Middle East to become a suicide bomber.
Information is still coming together as part of the investigation. There's more than one terrorist watch list and we don't yet know if the Orlando shooter was on any of them.
But the detail that's newly relevant is that even if the gunman was on all of them -- even if he couldn't legally purchase a plane ticket anywhere in the United States -- it wouldn't have made a difference when he tried to purchase the weapons he used to murder 49 people.
The NBC News report added, "That suspected terrorists can legally purchase weapons in the U.S. has been a fierce point of contention in Congress and among gun-control advocates."
And that debate is poised to begin anew.
In December, the Senate voted on a measure to prohibit those on a terror watch list from legally purchasing guns. Senate Republicans defeated the measure, and some vulnerable GOP incumbents -- including New Hampshire's Kelly Ayotte, Wisconsin's Ron Johnson, Pennsylvania's Pat Toomey, and Ohio's Rob Portman -- voted with the NRA and the far-right to protect the suspected terrorists' gun rights.
Florida's Marco Rubio, who's reportedly getting ready to run for re-election after having promised not to, went to pretty extraordinary lengths during his failed presidential campaign to insist that those on terror watch lists must be able to buy firearms.
In the wake of the Orlando massacre, expect Democrats to once more pursue this policy, while GOP lawmakers search for new ways to defend their bizarre position.