Mass murder has long been a grisly feature of human history. But the speed and extent of such massacres accelerated in the 20th century, with the spread of electronic mass media. First radio, then television and now the Internet, made it possible to more quickly spread and intensify the hatred and dehumanization of the victims necessary to get mass killings started. This was most vividly seen during World War II, when Nazi propaganda against Jews and Slavs, and Japanese propaganda against non-Japanese, made it easier to slaughter nearly 40 million people. The communists were even more successful in using electronic media to facilitate the murder of a hundred million "enemies of the people."
After World War II, there was much talk of preventing this sort of thing from happening again. But the communist propaganda continued to mobilize populations for mass murder, the most terrifying example being the Cambodian communists and their slaughter of several million "enemies of the people" in the 1970s. After most communist governments were swept away by popular movements in the late 80s and early 90s, it was thought that the age of mass murder was gone.
But it's still with us. In the 1990s, the communist police state in North Korea used all its propaganda and media resources to keep the population quiet and under control as ten percent of them (nearly two million) starved to death. China had carried out a similar feat in the late 1950s, as over ten million starved. Russia had done the same thing in the Ukraine in the early 1930s, killing over five million. So it should have been no surprise when, in 1994, Hutu radicals in Rwanda used months of intense radio propaganda, demonizing the Tutsi minority, and leading to the mass murder of nearly a million people. Around the same time, Serbs and Croats in the Balkans were using similar propaganda to support the slaughter of over 200,000 Bosnian Moslems. A decade later, the government of Sudan used electronic and print media to mobilize Arab nomads against African farmers in western Sudan (Darfur). To date, this has led to over 300,000 deaths and ten times as many African farmers driven from their homes.
So it's quite clear that the mass murders will walk among us. Many of them are still trying to make their genocidal dreams come true. That is, there are many parts of the world where the genocide-to-be is still in the propaganda phase. In fact, one of the largest media hate campaigns in the last century has not been able to generate a mass killing, yet. This is the anti-Semitic campaign against Israel and Jews. Ostensibly in support of the Palestinians (the local Arabs who tried to drive Jews out of what is now Israel), the campaign basically calls for the death of all Jews. The campaign began before World War II, and during the war, many prominent Arabs openly supported the Nazis and their murder of millions of Jews. Many Arabs still support the Nazi efforts, and hope to emulate them. The propaganda campaign has largely been restricted to Arab language media. But it's pretty clear what's going on, even for a non-Arab speaker. The visuals on many Arab web sites are unambiguous.
Some non-Arab media is also enthusiastically following the Arab lead. Iran is the most prominent example, but the hate campaign has become a popular media topic throughout the Moslem world. Criticism from the West, or foreigners in general, is generally shrugged off. Given the opportunity, there's no doubt these decades of hate filled propaganda could turn into another incident of mass murder.
The hate campaigns usually have political roots. The anti-Bosnian campaign in the Balkans came as a result of the breakup of Yugoslavia, and opportunistic politicians using the hate campaign to generate support for themselves. Politicians have long used ethnic animosities and the media to create an enemy that the politician can then offer to protect his people from. It's an ancient technique, made much easier with electronic media (especially when much of the population is illiterate.) This is the root of the anti-Semitic campaign in the Moslem, especially the Arab, world. Arab countries are largely run by dictators and monarchs. Arab economies are poorly managed and crippled by corruption and exploitation by self-serving national leaders. The populations are not stupid, and know that their leaders are the cause of most of the poverty and lack of freedom. But the anti-Semitic propaganda campaign does resonate, especially as it includes blaming the West, and non-Moslems in general, for the poverty and poor government. That's what al Qaeda is all about, the removal of corrupt Arab governments, and replacing them with righteous religious dictatorships. And if some mass murder will help the cause, as so often happened in the past, it shall come to pass.