one of the hardest books i have ever read was dictatorland by paul kenyon. basically, it's a book covering the rise of a number of infamous african dictators. after you read the first few sections and have learnt about the lives of a few of these dictators, you start to learn the pattern. they get involved in a resistance movement, usually against their colonial oppressors, they rise through the ranks of the resistance and are generally doing really good work. eventually, their country is freed and they become the leader of the country. everything looks great. but then the power gets to them and they start screwing over their countries in so many ways, just so they can get rich.
once you learn the pattern, the book becomes so much harder to get through. as you read the remaining sections, you read about more men who are fighting such noble causes and you root for them. but then you have to continually remind yourself that this man, who seems like the exact thing that this movement needs, will turn out to do horrible things. he will defraud his country; he will turn to corruption and bribery. all this hope that you had for this man and the resistance movement, even though you still recognise how absolutely necessary the movement is, gets destroyed.
i don't know what the conclusion is here, because hope is still needed and a fundamental part of any movement. but it's easy to see how people lose hope in any positive change happening when they've seen awful results of something that initially seemed so positive.
