This is a word that had already been escalating in popular usage in the years before the 2016 election, and that fact, not the election, is my backdrop here.
When therapists speak with therapists, we sometimes speak of "narcissisms," in the plural. The grandiose kind is not the only kind.
We all have narcissistic tendencies. Under the right circumstances, we all can act as if other people are good or bad objects and we the only real person in the world. Ever notice, when you're driving to work and worried about being late for an important meeting, everyone else on the road seems to be an asshole or an idiot? That happens to me all the time.
But many people, in ways ranging from subtle to explicit, are stuck too much of the time in a world in which other people are not thought of as having their own subjectivity, their own reasons for behaving as they do. I say "too much of the time" not as a judgment. It's more a measure of the way in which life doesn't go well thanks to this lack of empathy. Relationships flame out, careers get derailed.
Virtually no one comes to therapy saying, "please help me, I'm an incorrigible narcissist." Much more common is for someone to come to therapy saying, "my partner is an incorrigible narcissist." Sometimes this lay diagnosis is correct, sometimes not.
By no means am I saying that, if we could all understand one another, everything would be wonderful. People are different and want different things, and conflict and disappointment are unavoidable. But things are indisputably better when we have the capacity to understand and be curious about others.
I am reluctant to say that I treat narcissism. I treat people, and narcissism is often part of the picture, whether in a large or small way. It's always on my radar. Improvement in this area isn't painless, but it's always worthwhile.