IN a random, pitiless and, so far, motiveless act, the gunman aimed out of his 32nd floor hotel bedroom window at a mass of people a field away.
He was a former accountant; they were country and western fans, neither clan notorious for violence.
Yet, after 11 minutes of almost continuous firing, T-shirts became tourniquets and cowboy hats were strewn behind those who could still run.
At the time of writing, the death toll is 59, while over 500 have been injured.
The lack of obvious motive suggests that for some reason, 64-year-old Stephen Paddock just cracked.
This was the kind of random, everyday evil which happens when a man loses his mind.
In the USA now, that can have a terrible toll.
Eighty-five people die every single day from gunshot wounds.
The second amendment – the right to bear arms – is enshrined in the constitution in memory of the militiamen who fought the War of Independence in 1776.
Backed by the powerful National Rifle Association, there’s virtually no likelihood of it being repealed, despite the roll call of massacres.
Mr Obama barely tried; Mr Trump has yet to show his colours.
The gun lobby claims the shooters, not the weapons, are at fault.
But there’s no legitimate civilian use for automatic assault rifles, which can spray hundreds of rounds a minute.
The few gun control regulations which exist in states like Nevada, rely more on residency than suitability.
Mr Paddock passed all the vetting, acquiring a lethal arsenal of explosives, ammunition and at least 47 guns.
Many were found in his hotel room, where he smashed the windows in order to aim.
He killed himself, so we may never know what he was thinking.
But what allowed him to commit this atrocity were America’s lax, gun licensing laws.