This is a thread about the elements that go into persuading people. This is hopefully going to be limited to that topic in the ensuing posts.
People are persuaded by many things. Few of these are explicitly rational. There are often reasons but they are lost deep in the past and are only sometimes applicable to the current situation.
The way that most people operate is based on scripts when a full rational analysis of the situation will take up too much time or effort. This is not always a bad thing. That allows people to spot warning signs of a pattern. It does lead to the danger that people will bypass the study of the situation as they are overconfident from the answer their scripts give them.
A prime example is that of Serbia. People in the West were working off the "Nationalist Dictatorship" script and making assumptions about the situation without further information. Most predictions would have fit in the most famous case, that of Nazi Germany, hence an ideological expectation that there would be a repeat in Jugoslavia.
Despite information from reliable sources denying such occurrences, the Western media and diplomats were gullible enough to accept the continuation of the expected story from highly biased sources (Croats, Muslims, and Albanians). This accounts for the otherwise irrational actions of Western policy makers.
Other things need to be taken into account as well. Most politicians are narcissists. That allows them to be easily manipulated by whomever understands their psychology and can pull the levers of whatever the politician desires of himself. If Clinton wanted to seem heroic and compassionate, he would need to believe that the Serbs were evil so he could vanquish them (thereby proving his own heroism). People generally believe what provides the most emotional comfort unless the task of survival gets in the way.
People confronted with the situation on a day to day basis and whose survival depended on accurate assessments are less likely to lie to themselves. That accounts for the less anti-Serb attitudes of soldiers in Bosnia and Kosovo. Politicians are not there and thus may order whatever their ego needs.
People are attuned to accept whatever fits in their pre-existing framework. That is why people were more willing to accept the bombing of Serbia over Kosovo (supported by propaganda that has filtered through for years) than the interventions in Bosnia.
Another example is the response to Homosexuals getting beaten up in Belgrade. Many Westerners believe that Homosexual "rights" are demanded of democracies and everyone tends to judge people getting beaten up in the street as thuggish behavior. That feeds the impression that Serbs are undemocratic thugs and (given Croatia giving in to demands to permit such things) that Croats are not. That gives the impression even to those who already know the situation in the region.
People judge ideological frameworks based on how they explain the situation. The keep the ones (sometimes multiple, frameworks are not always exclusive) that serve their survival and psychological interests. By fitting into pre-existing expectations of the situation, a party can inadvertently be presenting a sound target for demonization.
An example. I hate rap. I argue the negative qualities of rap music to a man. Unknown to me, that man believes that rap is inherently linked to the black identity and views me as a racist. My statements then that I do not like American students are taken to be confirmation of that racism. It could just as easily fit in the context of someone who knows about the psychological impact of music but that is not what is expected.
For a demonized people, politeness, the absence of the expected markers (hatred, anger, rudeness, lack of respect), and reason forces people to either reevaluate or shift into a more favorable framework.
I argue the legitimacy of the Mugabe government in Zimbabwe with a Zambian man. I point out the shifting nature of territorial claims. He hears that but believes that is not relevant or the symptom of a racist mindset. I argue the existence of cultural differences that made British/Rhodesian rule better than Mugabe's. He thinks I am just another homesick Rhodesian. I point out the irrelevance of skin color to mental operations. He finally understands.
That worked because I was polite, respectful, logical, and could use many different examples to point out the lack of distinctiveness in the case and hence no reason to defend the ego.
Psychology matters in persuading people.