Today, in an art gallery in Ankara, the Russian ambassador to Turkey was gunned down as he was about to open an exhibition.

Andrei Karlov was several minutes into his speech when the assassin, 22-year-old Mevlüt Mert Altintas, stepped from behind and fired eight shots into the body of the 62-year-old ambassador.

“Don’t forget Aleppo, don’t forget Syria!” shouted Altintas, as Karlov fell to the floor.

“Allahu akbar! We are the descendants of those who supported the Prophet Muhammad for jihad!”

Altintas was later shot dead by police.

Now, everyone has a right to express their opinion – these days, it seems, even violently – and it’s clear the young assassin felt strongly about Russia’s involvement in the Syrian conflict. But Altintas’ oratory was let down by an all-too-common feature of terrorist incidents in the 21st century; the need to holler in a hoarse, high-pitched voice, as if the perpetrator is auditioning for an Arabic grindcore band.

There’s rarely any need for it, and that’s especially true in this case. Altintas was in an art gallery, of all things, and it’s clear from the footage that, once he’d emptied his heater, he had everyone’s undivided attention. There was even a microphone handy, vacated by the very man he’d just gunned down. If ever there was a stage prepared for a firm address elegantly delivered, this was it.

But it’s become de rigour in extremist circles to scream at the top of one’s lungs, reducing what might be a strong and sensible argument to a mere childish outburst. Take this video, for example, of terrorists engaged in a full-blooded chant. As a stirring call to arms it’s actually quite impressive – rhythmic, manly, unarguably intimidating – until about the 12-second mark when the leader starts shrieking like Janet Leigh in the shower scene from Psycho. It’s impossible for one who doesn’t understand Arabic to know what they guy is trying to say, but it might as well be “Leave Britney alone!” for all the menace it carries.

Abraham Lincoln’s Gettysburg Address is a speech that lasted no more than two minutes but which has resonated through the years, and not because Abe squealed it out like the dude from Rage Against the Machine. He spoke confidently, measurably, and, today, his message is as fresh as it was back in 1863. By contrast, his assassin, John Wilkes Booth, shouted his message after he killed the President at a packed Fords Theatre in Washington two years later and, today, nobody can agree on what he said. There’s a lesson in that for all of us.

It might seem petty to focus on such a cosmetic feature of what amounts to an act of slaughter, but jihad, whatever else it might be, is a battle for hearts and minds. From a recruitment perspective alone, behaving like you’ve lost your marbles is no way to instil confidence and ease in prospective apprentices. Ask anyone in your Human Resources department and they’ll tell you that shouting never gets you anywhere. It’s also unhealthy.

In other news today, a suspected terrorist has driven a truck into a market in Berlin, killing at least nine and wounding many, an event that will doubtless keep newspaper opinion columnists busy for the next few weeks, despite there being nothing much to say about an act that is clearly, grotesquely insane.