On one level, the officials said, he is something of a laughing stock among Europeans at international gatherings.
But behind the mocking, there is growing fear among international governments that Trump is a serious threat to international peace and stability.
“He’s not the kind of person you can have a discussion about how to deal with [Fayez] al-Sarraj [the prime minister of Libya]," the official added. "So you look for people around him, and that is where it’s a problem: The constant upheaval, it’s unclear who has influence, who is close to the president."