Let’s agree to disagree on the use of the descriptor “diplomatic,” as in “she’s very diplomatic in how she handles idiots at work.” of diplomacy. In other words, diplomacy may be a formal mode of negotiation, an alternative to military conflict, or even an organizational bureaucracy/process (“let them handle it diplomatically”).
To wit, its not really about being “nice” to people.
Kim, who is currently chief of staff to Deputy Secretary of State Antony Blinken, questioned the widely accepted meaning of the word “diplomatic” as nice and tactful.“It’s not about being nice to people or not saying hurtful things. In fact, in the jobs that I’ve had to do, we’ve had difficult and sometimes combative conversations,” she said. “In the most acute cases, like North Korea or Iraq, it’s about talking to someone so that guns don’t get pulled out. It’s a way to avoid or end conflict, and to get people to compromise.”
Source: Diplomats in the Trenches: ‘Diplomacy Isn’t About Being Nice to People’ | HuffPost by Nicholas Kralev