I’m not sure when or why “nice” became a near-insult and the condition of being nice became something to avoid or to apologize for. Etymology might explain the current attitude; the word is derived from the Anglo-Norman nice, nis, nise, Old French nice, and classical Latin nescius, all of which carried the meaning “foolish, silly, or ignorant”. But those meanings are now obsolete, and even if the semantic changes are unclear, since at least the late 18th century, “nice” has carried the meaning, when describing a person, of “pleasant in manner, agreeable, good-natured; attractive.” I see nothing in that definition to merit contempt. And I doubt that most of those who sneer at the word know about its etymology.
Many of us can recall parental cautions to “play nice” with siblings or other groups of children. Perhaps you have issued this instruction to your own children. Children, of course, can be unrepentant savages uninterested in considering the feelings of others and not yet aware of the rewards kindness holds for giver, receiver, and the surrounding world. But we are no longer children. We know that those who see being nice as weak and hypocritical create pain and humiliation for others, leaving a legacy of anger and resentment that sooner or later will rebound.
Recently a few trusted friends and I were discussing this issue, and one said, “I’m sick and tired of seeing ‘being nice’ derided as some kind of cowardly impulse. Being nice is HARD.” Indeed, it is. Ignoring the feelings of others is easy. Saying what we feel with no consideration of how our words affect others is easy. Giving into an impulse that lets us feel superior is easy. It’s instant gratification—but at a cost. It's always easier to be snide and snarky and congratulate yourself on your own cleverness than it is to care about how others feel and to avoid dumping more negativity into the world.
The power of nice is not about running around maniacally smiling and doing everyone's bidding, all the while calculating what you'll get in return. It's not about being phony or manipulative. It's about valuing niceness--in yourself and in others--the same way you respect intelligence, beauty, or talent. Niceness is a powerful force.