Source: Education and the Social Order, 1932, chapt.15: Propaganda in Education

( The sentiment of Roman Catholics for the Church is bound up with the emotions that they felt in youth at midnight mass, at the solemnity of Good Friday and the joyfulness of Easter, at incense and darkness and mystery. When strong childish or adolescent emotions of this sort become associated with a political group, they may, and often do, generate a sentiment which is capable of overriding all intellectual convictions. This form of propaganda is best understood by the Catholic Church, which has had nearly two thousand years in which to perfect its technique. But the same sort of thing is done, though less perfectly, by national States, in such forms as martial music and military displays. In my childhood, British soldiers still wore the traditional red coats, and I remember vividly the delight of seeing regiments on the march. Such delights tend, unless counteracted, to produce a belief in militarism. Emotional propaganda has several dangers. In the first place, it is just as easily used in a bad cause as in a good one, perhaps more easily. ...
Another danger of emotional propaganda is that it tends to close the mind to argument. The conscious mind may be rational, but just below the level of consciousness unalterable convictions remain from early years. Many men, in quiet times, are internationalists and freethinkers, but when there is danger of war or death they become patriotic or religious. )