Ratko Mladić, the Serb commander who presided over the murder of more than 8,000 men and boys at Srebrenica in Bosnia, will die in jail.

After a twenty-year wait for justice, relatives of those killed during the 1995 genocide watched Mladić – the so-called 'butcher of Bosnia' – scream and shout as he was dragged from the courtroom in The Hague by police officers.

Read more Inside the Bosnian village where Ratko Mladic will always be a 'hero'

This represented something resembling justice, but it also represented the closing chapter of a colossal failure of Western statecraft. Since the genocide and the preceding war in the former Yugoslavia, Serb aggression has been richly rewarded in terms of the 'facts on the ground'.

Large chunks of Bosnia are now swallowed up by the ethnically homogenous Republika Srpska, a statelet created on the bones of dead Bosniaks and given legitimacy by Western leaders in the 'peace' framework of the Dayton Accords.

Dayton was of course only the final capitulation to the racist nationalism of Serb commanders like Ratko Mladic and their political backers, the most high profile of whom were Radovan Karadzic and Slobodan Milosevic. British statecraft had been dragged through the mud by the government of John Major's Conservative Party much earlier.

Throughout the Bosnian war, British diplomats worked assiduously to halt the imposition of a NATO no-fly zone to protect Bosniak civilians. When it could no longer do that, the British Foreign Secretary Douglas Hurd, who former Tory Prime Minister Margaret Thatcher once said would "make Neville Chamberlin look like a warmonger," sank deeper into the moral sewer by trying to obstruct its implementation.

Britain wasn't going to help because, as Hurd put it in a twist of the Thatcherite mantra, there was "no such thing as the international community".

Once news of the bloodbath at Srebrenica did begin to leak out, the British state even tried to block humanitarian action. According to the journalist John Sweeny, "the British Ministry of Defence went on the offensive working to deny and play down evidence of the massacre."

The besieged Bosniaks got little help from the United Nations either. The genocide occurred in one of the UN's so-called 'safe havens', with 400 lightly armed Dutch peacekeepers deployed to protect Bosnian Muslims.

Yet when Bosnian Serb forces under the command of Ratko Mladic reached the town, Dutch forces capitulated immediately. Worse, in an echo of Dutch wartime collaboration — the Netherlands saw one of the highest levels of collaboration of any Nazi-occupied country during the Holocaust — Dutch peacekeepers denied Bosniak fighters the return of weapons they had surrendered, forced them out of a UN military base in the town and handed them over to Bosnian Serb troops.

Read more Ratko Mladić guilty verdict is welcome, but Bosnia is still 'full of butchers' like him

The Dutch had apparently received 'assurances' from the would-be murderers. The soothing peace talk had come from General Mladic himself, who three days earlier had amicably dined on suckling pig with the commander of the United Nations Protection Force in Bosnia (UNPROFOR), General Bernard Janvie.

Prior to that, as the casualties in Bosnia mounted, UN General Secretary Boutros Boutros-Ghali had dismissed the conflict in Bosnia as a "white man's war".

While Bosnia descended into hell, its own government turned to Islamic countries for practical assistance and radicalized paramilitaries swept in, allowing isolationist onlookers in Britain and America – as with Syria today – to slander the Bosniaks as 'extremists' and wax high-mindedly about both sides being as bad as each other.

Meanwhile, at the time of Mladic's crimes, a section of the left, with its misplaced nostalgia for Tito's authoritarian dictatorship, strained every sinew to portray the Serbs as plucky underdogs who were being demonised by an 'imperialist' West.

After the massacre at Srebrenica British foot-dragging ceased to matter. In August 1995, with thousands of Bosniaks already dead, NATO finally launched its Operation Deliberate Force, the massive bombing of Bosnian Serb targets which forced the latter to the negotiating table.

Yet by any measure military intervention had come altogether too late (the British had made sure of that) and could not bring back life to the bullet-riddled bodies tossed in unmarked graves; nor assuage the pain of grieving relatives.

Read more 'Butcher of Bosnia' Ratko Mladic guilty of Europe's biggest genocide since the Nazis

Bosnia is a historical crime that, like many other historical crimes, we are content to be correct about in hindsight.

There are still a few cranks out there who peddle the notion that the Serb leaders were misunderstood and engaged in some sort of anti-imperialist enterprise. But most people assign the widespread slaughter of Bosniak civilians in the 1990s to the categories of 'tragedy' and 'crime'.

The same will probably one day be said of Syria. It too will represent both a 'tragedy' and a 'crime' in the eyes of well-meaning people.

Yet 'never again' is often more an exercise in performative pathos than a genuine admonition to put a halt to mass murder. Western countries could have put a stop to Serbian imperialist aggression in Bosnia; they consciously chose not to for reasons of realpolitik with a side-order of racism directed toward Bosnian Muslims.

In the end, as much as we may celebrate the bringing to justice of Ratko Mladic, we should remember that the Bosnian Serbs were given the green light for their brutal onslaught by the cynicism of Western - largely British - politicians.