the difference between right and left arises out of a separation of virtuous, deserving, human Self from parasitic, evil, dehumanized Other. You do that, you easily accept actions, both passive and active, against the Other that you wouldn't perform or tolerate against Self. Righties who occasionally don't do this can be worked with a bit. But we're in a time when the right demands purity.
You look at rightie positions, and, on the surface, they're flagrantly inconsistent. But look on Self/Other level, they make perfect sense. The pursuit of power for Self--deserving of it, virtuous in its exercise of it--and its denial to Other. Even such elementary exercises in social and political problem-solving as trying to explain (NOT justify) antisocial actions are seen as undermining the Self/Other narrative, and are thus rejected as weakness, appeasement, moral turpitude and un-American. Consider, in this context, the extraordinary notion that talking diplomacy should be reserved only for our friends, and our enemies engaged with aircraft carrier battle groups as the default tactic.
There are philosophical, even rigorously logical reasons to reject the centrality of Self. It's inevitably self-referential, both as I've defined it and as is any rigid ideology, and doomed to incompleteness and error in depicting reality. The record of dehumanizing one's opponents, denying their very legitimacy in debate, is and has been consistently destructive, enabling of the worst of humanity, and, in point of fact, projected onto the left most vociferously by those holding thus on the right, while far more characteristic of right than left. A prescription for political, even economic failure, all that.
So there's Ayn Rand, who's about nothing if not this. Libertarians, who can't imagine themselves bereft of the tools to actualize themselves, who acknowledge not at all the centrality of contingency to human life. A denial of a social contract extending to any other than Self.
Meanwhile, the left, while acknowledging right and wrong, acknowledges a common humanity, in service of recognizing problems' causes and solving them. And, more crucially, perhaps, acknowledging the certainty that every human being, including ourselves, will sometimes be mistaken, and that all of us are capable of evil, and must act towards each other mindful of the fact. There's no more important conclusion to draw from the history of the Nazis, arising in the country of Goethe and Bach, and the all too common other examples, historically and contemporaneously, of atrocity committed by ordinary, average people. To the extent that the left accepts that, it's capable of better governance across the board than the right, even pragmatically. When the left hasn't--it has happened--not so much. The cynicism with which righties dismiss 'liberals', whatever they are, and 'liberal' attempts to solve problems rather than find fault and oppose the Other implacably and mindlessly, is both a self-fulfilling prophecy and guarantees that they, to some extent, wind up emulating the very monster they claim to be fighting.
I could play this game all day, but you get the idea...