In fact we often ascribe blame wrongly because we ignore the effects of group dynamics in the case. Religion is a great example. I've been reading about the Islamic prophet Mohammed, for example. In the early days following his life-changing experience, when he believed that he had been approached by an angel bearing messages from God, Mohammed would engage in novel ways with his community, in the trading town of Mecca. Part of his dissatisfaction lay in his perception of economic inequality based on things that he saw in the town, and early converts to his doctrines tended to be those who belonged to the parts of that community that were economically and politically disenfranchised; in this way, Islam closely resembles Christianity. The town's elites were unhappy with changes to the status quo that he was proposing and Mohammed found that it was necessary, for his personal safety, to leave town, which he did, travelling to another town named Medina. The wars that many people often deploy in their rhetoric to attack Islam started with this shift of location, as Mohammed worked to build solidarity inside Medina while continuing to preach, and while staring down threats that continued to come from Mecca. Eventually, Mohammed mobilised an armed force in Medina and fought the Meccans. But it wasn't religious doctrine that caused the struggle, it was group dynamics. Mohammed's novel doctrines - his insistence on honouring one God as opposed to the polytheism that was traditional for Arabs, and his economic philosophy that worked to the detriment of the rich and in favour of the broader community - worked geopolitically and at the level of the local community to set up a process of othering that led, inexorably, to war.
Cynics will say that othering is often performed in order to generate coherence within the polity, and this is how the early wars of Islam can be understood. But often in order to make change it is necessary to mobilise scattered individuals under a single banner - or, as it's also called, a 'standard' - and so othering can definitely have a positive goal. It's all a matter of what you are trying to achieve. Nationalism is a classic form of othering - my earlier example of England and France belongs to this class - and, again, it can have both a positive and a negative connotation.
But when it disadvantages the weak othering has to be condemned - as in my first example of the boys on their bikes hurrying down the street where I was walking along minding my own business. Groups of young men inspire feelings of unhappiness for this reason, as their only goal can seem to be to generate cohesion within their group at the expense of the lone outsider. There are so many examples from history where a single individual has had to combat disinterest or even downright hostility, on the part of the majority, and the case of Mohammed is one of these. But there are many others, and for devotees of progress - the children of the Western Enlightenment (Islam can be viewed as a tonic moment in a kind of Middle Eastern Enlightenment) - a host of examples combine to form a revered hagiographic classis containing such names as Copernicus (science), Hus (religion), Wollstonecraft (human rights activism), and Coleridge (art); possibly early Romanticism - with its roots in revolutionary democracy - remains a dominant moment in the shadow of which we still live, intuit, and perform our acts of individual thinking and creation.
In a sense, the Romantic moment contains a paradox: where capacity is built by a group in order to enable individual autonomy and to empower the individual to achieve his or her own goals. A similar paradox adheres to democracy itself: universal agreement as to the equal status of every member of the polity. That this common feature adheres to both democracy and Romanticism - they're both paradoxical - is interesting, as well, as it seems to promise the end of the group, of othering, and of orthodoxy itself. In the absence of orthodoxy the individual agrees to respect the aims and values of every other individual, but will othering ever completely disappear? If every opinion has equal value (the Blob) then the only valid goal is personal enrichment. But this outcome promises new challenges, new reasons to mobilise in the face of new sources of economic inequality, and new instances of othering.