What it means to be "evil", or carry out "evil" acts, is a morally-loaded question, but the most generally-accepted answer is that "evil" behaviour deliberately harms other people, and humanity in general.
It is commonplace to describe people such as Adolf Hitler, Osama Bin Laden, and Pol Pot as "evil", because they deliberately sought to kill and persecute people. But what is more specific is that these individuals had a skewed view of morality that allowed them to justify acts that any sane person would instantly call evil and immoral. In other words, these individuals were all psychopaths, because their view of morality was either absent entirely, or so far from the norm as to be unrecognisable.
I talked recently about two types of sadism. Firstly, the sadism of an amoral psychopath, who makes decisions based purely on their relative merit to themselves, regardless of the consequence on others; this is simple amorality, where "morality" doesn't enter the equation, and decisions are a simple and heartless cost-benefit "calculation".
Secondly, I talked about a more malignant sadism, which combines "sadism" with "pleasure": the enjoyment of others' suffering. This is another form of psychopathic sadism, but where the suffering the psychopaths causes is to create personal satisfaction (like Hitler's persecution of the Jews, or OBL's desire for "jihad" against the West).
I bring this point up again to clarify what I therefore see as two forms of "evil" (or sadism) that exist, and how they are implemented; one whose basis is largely ideological, and another that it largely emotional.
Amoral Sadism as an Ideology
It's said by some that Capitalism is "evil". But what this really means is that Capitalism is amoral. There is no "moral code" written into the economic theory, because the purpose of Capitalism is the pursuit of profit. While some have made some mealy-mouthed attempts at justifying its effect on humanity, its most famous contemporary ideological thinker, Ayn Rand, was much more straightforward in the clarity of her logic. And in spite of Capitalism's obvious amorality, she counter-intuitively argued that Capitalism was the only moral form of economic ideology because it best represented the principle of human freedom at its zenith.
Rand's perspective turned morality on its head, as well as inside out, as I've said before. For Rand, any ideology that imposed limits on a person's personal freedom of choice was immoral. Using this thinking, it made almost all government actions immoral by definition, except for the role of defence against invasion and applying an agreed rule of law. Paying taxes for any other government service, therefore, was an immoral act, according to Rand, as it forced people to pay for services they didn't knowingly choose (as government would here choose how to spend the money, not the individual); in other words, tax was equated with theft.
Not only that, but Rand said that altruism was evil, because any "help" from outside imposed another's will on individuals, and took away the chance for someone to find money by their own means (as was therefore psychologically damaging to a person's self-confidence). So not only does this ideology pit the individual against the collective will, it also turns selfishness into a virtue, and charity into a vice.
Rand's view was that improvement in society came about only through the actions and decisions of individuals, and that the only rational way of living was to view everything through self-interest. Doing things for the benefit of others was not only illogical, in her view; it was also immoral. Like the cynicism of a psychopath, Rand believe that a rational person would only do something if it was for their benefit; the only "morality" of a decision was if it was advantageous or not, not what its effects on others would be. This is how Capitalism is comparable with amoral Sadism: Rand made Capitalism's mindset equivalent to that of a psychopath.
In Rand's view, poverty caused as a result of Capitalism was therefore inevitable, but also government or collective action to alleviate poverty was wrong because it took away the individual's chance for self-improvement. Better that a poor person learn through their own errors than be given a hand-out. Rand saw American Capitalism as the exemplar of this system, as it had thrived on the back of unrestrained Capitalism, but also fed an ethic of proud self-reliance into even the poorest.
The irony here is that it makes the poor celebrate the rich as Ubermensch, while the rich have no incentive to care about the poor.
The supposed "ethics" of Rand's ideology (Objectivism) are simple cause-and-effect: a self-reliant person in a self-reliant system would quickly want to improve himself, as his empty belly would quickly remind him. For all Rand's clever words and counter-intuitive logic, the system she is advocating is only one step higher than anarchy, except that the government maintains basic law and order. With the rich already secured in this system, it is therefore almost equivalent to the preconditions for Fascism.
Rand was a vociferous critic of Communism (as well as Fascism, even though her ideology has resulted in more-or-less the same effect). But what Rand shares with Communism is an amorally Sadistic mindset. What the CEO of a multi-national company and Stalin have in common is an amoral focus on goals. Whether the goal is to maximise profit or maximise grain production, the mindset is the name; the only difference is in the detail of the method. While a sane CEO wouldn't set about systematically eliminating his workforce (like Stalin did when he slaughtered millions of rebellious peasants), he certainly wouldn't flinch at firing them if it was financially prudent to do so.
Besides, in many ways, a private company is no different from a dictatorship. The most important thing is keeping the stock prices up and the shareholders happy; both these are achieved through the maximisation of profits and minimising costs. Morality doesn't come into it, unless it's advantageous for the company's image (when "enlightened self-interest" comes into the equation). All that differs are the details; the principles are the same. This is where the skills gained from business become relevant in the field of politics and government.
Malignant Sadism as a mass emotion
I've said that Amoral Sadism, as a form of evil, is evident in Capitalism as well as Communism. Malignant Sadism, on the other hand, is a more emotional and hate-filled form of evil. While Amoral Sadism is cold and heartless, Malignant Sadism is angry and vicious, filled with blood-lust.
This form of "evil" comes from a more primal root; the love of the self and the hatred of the "other", as well as a fetishisation of violence itself. Bound up in this is the sense of victimhood, tugging on the emotional aspects of the brain. Whereas Amoral Sadism is more ideological, Malignant Sadism as a mass emotion stems from the ideas of nationalism and religion.
"Morality" in this form is interpreted in more emotional terms, so therefore requires little intellectual justification. Amoral Sadism is able to bypass this issue of "right and wrong" by saying that it is irrelevant; this type of mass Malignant Sadism bypasses the intellectual issues over "right and wrong" based on simple nationality and creed.
Hitler is the most famous example of this in the 20th century, using nationalism as an excuse for evil. More recently, massacres have occurred in Rwanda based on nationalism, as well as in the former Yugoslavia, based on nationality and religion.
Then there are the countless religious wars over the centuries, justifying evil in the name of God. Osama Bin Laden is but the latest example of this, as Al-Qaeda and its affiliates use the religious scripture as justification for mass murder, deprivation and tyranny. The Catholic Inquisition was responsible for mass torture, and so on.
Nationalism and religious fanaticism are the main exemplars of mass Malignant Sadism, as they are both inherently narcissistic creeds, and enjoy visiting violence upon their enemies. For them, violence against the enemy is righteous, and therefore to be encouraged and praised. This is the difference between this form of "evil" and amorally-sadistic Capitalism, for example.
But evil will always find a name for itself.