The beautiful Siwa Oasis in the far western deserts of Egypt is a remarkable place, for multiple reasons. It’s probably been inhabited, continuously, for 12,000 years. Alexander the Great came here to consult the already renowned Oracle of Amun-Ra in 332BC (some say he is buried here, as he loved Siwa so much). You can swim in Roman cisterns fed by one of the 300 natural springs – which also nourish thousands of date palms and olive groves. The locals have their own Berber language – Siwi – spoken nowhere else on earth.

But there’s one facet of Siwa’s history which is less talked about. Within living memory, they had black slaves here, generally fetched from further south in Africa, and trafficked along Saharan routes trodden by Muslim pilgrims, ultimately heading for Mecca.

If we do anything we should focus on the slavery that still exists – inside the Islamic world and far beyond

As I read about this nugget of history, last week –  sitting on the stunningly silent, mud-brick balcony of Adrere Amellal, a hotel which overlooks the oasis – it jarred quite hard with a news story I’d read an hour previously. Namely, that politicians in California are proposing to pay reparations to black Californians who can prove they descend from slaves. The sums being discussed are not trivial. The official taskforce has decided that entitled individuals should each get up to $1.2 million (£955,000); others say this is nowhere near enough, and every individual should get $200 million (£159 million) – that is not a typo.

Clearly, reparations on almost any scale will be brutal for the Californian budget, whatever Californians democratically decide. The idea is therefore proving controversial. But, from the perspective of Siwa, Egypt, and Muslim North Africa, the entire debate about slavery, in the West, is beyond controversial, it is bizarre, myopic and insanely one-sided. A form of moral solipsism.

It is as if slavery only ever existed, and only really matters, when done by white Europeans to black people and across the Atlantic to the Americas. The truth, though, is that slavery has been practised everywhere by everyone in every century. In particular, slaving has been practised with great eagerness by the nations and societies of the Islamic world, for time out of mind. This was going on long before the first Portuguese slavers shipped black Africans from little Lagos on the Algarve to the fevered coasts of Brazil.

Slavery is such an intrinsic part of Islam that the treatment, utility, and social status of slaves is expressly discussed in multiple verses of the Koran. Notoriously, the Koran allows slave owners sexual rights to their female chattels – the woman is not permitted to refuse. This fact was exploited by Isis terrorists when they seized Yazidi girls as unwilling concubines.

With this divine approval of slavery, it is therefore unsurprising that Islamic societies took to slaving with gusto from the outset, as they conquered their way across Europe, Africa, and Asia. In Africa, Islamic imperialists were especially zealous. Whereas the evil white European trans-Atlantic slave trade transported maybe 12 million people from Portugal, Spain, Holland, Britain, France etc to the Americas over 400 melancholy years, various khans, sultans and emirs forcibly imported possibly 15-20 million black Africans to the Maghreb, Arabia, and so forth. No one is entirely sure of the number, but it is big.

Indeed, not only was the Muslim/African slave trade likely larger in numbers taken, it began much earlier, and went on far longer – perhaps 1400 years – and it was arguably even crueller. Why crueller? Because Muslim slavers castrated, brutally and automatically, so many of their male captives. They did not even care to breed them. Black African male slaves dragged by Muslim traders along the many interiorcross-desert routes, or bought on the Swahili coast, were infertile human mules to be used and then dumped. A visit to the dreadful Muslim slave pens in Zanzibar – one of the most claustrophobically evil places on earth – will give any visitor a sense of this fierce sadism, that endured over a thousand years.

And that, of course, is just Africa. While white Europeans restricted themselves almost entirely to the trans-Atlantic trade, Muslim slavers ranged widely across Europe, Asia, anywhere. Barbary pirates – like the infamous Salé Rovers – took white slaves from Italy, Spain, France, Britain, Bosnia, Croatia, Russia, even America, well into the 19th century. At least a million white slaves were seized in total. In England they particularly preyed upon remote coasts like Devon and Cornwall – humble fishermen out of Penryn, or Polperro, if they got unlucky, could end up as helots building the lavish palaces of Islamic Morocco.

At the same time, Muslim conquerors in south Asia were busy enslaving many millions there: a sense of the scale is given by particulars: eg, just one Delhi Sultan, Alauddin Khalji (died 1316), is said to have owned 50,000 slave boys, and 70,000 construction workers. Further south, Muslims across Indochina enslaved indigenous peoples, en masse. And of course, everywhere in the world, Muslims voraciously hunted for young white-skinned female slaves for sex. Circassian girls in the Caucasus were particularly prized; it was once claimed that Egyptian royalty might have died out if the caliphs had not had pale-skinned green-eyed Circassian girls to keep their ardour sharpened.

It’s a grim history. Yet no one has ever really sat down and totalled the number of slaves taken by Islamic nations and societies. It could be double the numbers of people enslaved by western Europeans since Columbus.

In fact, and if anything, we tend to actively diminish Islamic slavery. We minimise it, ignore it, or defang its nastiness. For example, if you try Googling the words ‘Islam’ and ‘slavery’ you get – first result – mealy mouthed pap like this from the BBC: ‘Islam treated slaves as human beings as well as property. Islam banned the mistreatment of slaves – indeed the tradition repeatedly stresses the importance of treating slaves with kindness and compassion. Islam allowed slaves to achieve their freedom and made freeing slaves a virtuous act.’ Islamic slavery is seen here as practically an act of kindness. There is no mention of wholesale castration and rape. And certainly no mention of reparation.

So why do we have this insanely one sided view of slavery? Even though slavery was not abolished in half of the Islamic world until the 20th century (in Mauritania as late as 1981)?

Perhaps it is because Muslims are not wallowing in Muslim guilt, and are therefore immune to being guilt-tripped. Perhaps it is because Muslims do not have a special class of academics, weaponising ‘intrinsic’ Muslim evil against Muslims themselves.

Instead, they have accepted that horribly bad things occurred, on a literally imperious scale, but the only sane solution is to draw a line. Slavery was an evil thing, it happened everywhere, but we cannot alter the past: we move on. If we do anything we should focus on the slavery that still exists – inside the Islamic world and far beyond.

Siwa itself is a good example of a place that has moved on. Black people are a fairly common sight, many of them are descendants of slaves. There seems, to this outside observer, to be little anger or resentment. Life endures – and sometimes improves. ‘Cleopatra’s spring’ still bubbles away in the shade of the date palm. And from this timeless perspective it is California and the wider West that, apparently, needs emancipation: from its delusions, its self-absorption, its ecstasies of grief and its moral orgasms of remorse – and its crazy belief that folding money and statue-toppling can repair history, while ignoring the actual history of the world.