On Sunday night in the United States, a gunman opened fire at a music festival in Las Vegas from the 32nd storey of the Mandalay Bay hotel. Details are still hazy in places, but the death toll currently stands at least at 58 people, while a further 515 are injured. The Las Vegas attack is now the deadliest mass shooting in American history.

The previous record was held by the shooting at Pulse, a gay nightclub in Orlando, Florida, in which 49 people were killed. Similarities between the two are striking. Both featured military-grade assault weapons, used against crowds at music venues – the wanton slaughter of people at play, listening to music. An attack on the pursuit of freedom. Our very way of life, as the saying goes.

In the initial reporting, authorities in Las Vegas declined to call what happened a terrorist attack. “No, not at this point,” Sheriff Joseph Lombardi told reporters when asked if the act was being considered at such. The shooter was a 64-year-old white man called Stephen Paddock, a small-town Nevada local, and it was unclear to the media what narrative to append. Islamic State has claimed the shooting, but the usually opportunistic Donald Trump did not repeat the claim in his speech. Clark County district attorney, Steve Woodson, said: "This doesn't involve politics."

What do we call “terrorism”? The word wasn't widely used after the 2014 shooting at Isla Vista, California, where a young man was radicalised online not by Isis, but by trolls and misogynists. Or after the attack on black congregants at Mother Emanuel church in Charleston. Or the massacre of children at Sandy Hook elementary school. Common elements: white men, assault rifles. And terror, of course, in the literal sense. But none of those perpetrators were widely referred to as “terrorists”.

It has become a dark joke at the expense of American media that when a white man kills, articles will quote neighbours describing him as quiet, polite, someone who “wouldn't hurt a fly”, while when a person of colour is killed – like Michael Brown, whose death at the hands of a white policeman sparked the Ferguson protests in 2014 – articles will say he was “no angel”. In Orlando, the shooter, Omar Mateen, was born and raised in New York, then Port St. Lucie, Florida, and was every bit as “local” as Paddock. Yet as soon as his Muslim origins were known, he was labelled a terrorist.

To the right wing, this looks like liberal language-policing. But the words are important in what they reveal about American society. It is a deep-rooted linguistic double-standard. “Only in America,” the Black Lives Matter activist Shaun King tweeted on Monday, “can whiteness prevent the man who conducted the deadliest mass shooting in American history from being called a terrorist”.

Right-wing pundits also complain that anyone asking hard questions in the wake of mass shootings is “politicising” the tragedy. That's straight out of the gun lobby playbook - you can only offer thoughts and prayers, not solutions that might have prevented the terrorist from obtaining military armaments. The right would like us to believe that only terrorist attacks are political, and only political attacks are terrorism, which invariably, in the post-9/11 age, means the ethno-nationalist political terror of radical Islamist groups.

But that position is meaningless. An attack like the one last night in Las Vegas is inherently and by definition a political act. Even setting aside motive, the fact that the gun used to kill 58 Americans and injure hundreds more was purchased in a country where such military-level weaponry is freely available to citizens – that's a political position. In Isla Vista, the killer wanted to terrorise women. In Sandy Hook, children. In Mother Emanuel, people of colour. In Orlando, the LGBTQ community.

All attacks of this nature, whatever the race or creed of the attacker, are acts of terror. The Nevada statute on the definition of the word is clear. The act is its own context. There is no disentangling the motive from the meaning. And as we grieve, we must also face the difficult questions that it raises.

If not, then we will be trapped in this endless loop of butchery and sophistry, for ever.