Noam Chomsky:

We should not underestimate the capacity of well-run propaganda systems to drive people to irrational, murderous, and suicidal behavior. Take an example … World War I … on both sides, the soldiers marched off to mutual slaughter with enormous exuberance, fortified by the cheers of the intellectual classes and those who they helped mobilize across the political spectrum, from left to right including the most powerful left political force in the world, in Germany. Exceptions are so few that we can practically list them, and some of the most prominent among them ended up in jail for questioning the nobility of the enterprise: among them Rosa Luxemburg, Bertrand Russell, and Eugene Debs. With the help of Wilson’s propaganda agencies and the enthusiastic support of liberal intellectuals, a pacifist country was turned in a few months into raving anti-German hysterics, ready to take revenge on those who had perpetrated savage crimes, many of them invented by the British Ministry of Information. But that’s by no means inevitable, and we should not underestimate the civilizing effects of the popular struggles of recent years. We need not stride resolutely towards catastrophe merely because those are the marching orders.