Tolstoy once said that, although all happy families were pretty much alike, each unhappy family was miserable in its own peculiar way. Today it is becoming clear that although each genocide has its ghastly specificity, the west's responses are remarkably similar.
The population of Darfur now faces an attack on its existence, not only by the infamous Janjaweed militia, but also by Sudanese regulars. This is not a religious conflict, because both "sides" are Muslim. Rather, the black Africans of Darfur are being subjected to calculated ethnic persecution by the Arab - and Islamist - government in Khartoum.
Western governments' responses to this crisis closely follow a pattern established with Bosnia between 1992 and 1995, when radical Serb nationalists sought to carve an ethnically "pure" Greater Serbia out of the ruins of Yugoslavia.
Then as now, the first line of defence was denial, accompanied by attempts to blur ethnic distinctions, though Khartoum makes no secret of its desire to create an Arab-dominated state. Its agents traffic black people as slaves and literally brand women.
The second line of defence is "moral equivalence". With Bosnia, our government refused to accept a real distinction between the legitimate government in Sarajevo, upholding a multi-ethnic ideal, and those seeking to destroy it. Today's spokesmen for the Department for International Development often suggest that the Darfur rebels are equally responsible for the violence, though we know that Khartoum and its proxies are to blame for more than 90 per cent of the deaths in the region's conflict.
Then comes something we'll call "humanitarianisation". In Bosnia, western governments tried to turn a crime that required a military response into a humanitarian "tragedy", which could be alleviated by sending aid. So the international community has provided various "band aids" for Darfur, but not the major surgery needed for a resolution to the crisis.
Only military intervention by western countries can provide security now, but again we hear echoes of Bosnia. While important parts of the proposed Anglo-US resolution on Darfur fall under Chapter Seven of the UN Charter, implying a mandate to enforce, all the rhetoric stresses the need for consent from Khartoum. This relegates the resolution to a "consent" mandate under Chapter Six. Some of these same western governments used similar jiggery-pokery to reinterpret Chapter Seven mandates on Bosnia as "Chapter Six and a Half" resolutions, which left them powerless to stop ethnic cleansing.
Western governments are not doing this out of deliberate moral turpitude. An important factor is a presumption in favour of strong states, even harsh ones, and against separatist movements, which are perceived as agents of instability.
This is a misunderstanding. The core problem in Sudan is not separatism, but Khartoum's attempts to marginalise groups in Darfur as it builds a state on Arab chauvinism and Islamism. It is yet another echo of the former Yugoslavia, where the west failed to grasp that the main problem was not peripheral nationalisms but "central secession" - the Serbs bailed out of Yugoslavia first.
All this should be of interest to Gordon Brown. With diplomatic action advancing so slowly, Brown may yet find that Darfur is his first big foreign-policy challenge as prime minister (provided Khartoum has not finished its dirty work by then). Brown has tended to view Africa's problems as relating principally to international development, but Darfur may confront him with those issues of humanitarian intervention that he has spent ten years ducking.
Demonstrate at Sudanese embassy, London SW1, then march to No 10 on 17 September, 11am