Mr. Kim’s lightly striped jacket came with a matching tie and slacks. His trademark hairstyle was carefully coifed, and in a twist, it was shorn above the ears, leaving what has been dubbed a “trapezoid shaped” haircut.

The soft tones of his outfit did not carry through to his message, in which he boasted of having “a nuclear button on the desk in my office.” And it stood at stark odds with the reputation of a leader who is suspected of ordering the assassination of his half brother with VX nerve agent, having his uncle and mentor killed with antiaircraft machine guns and running a state security apparatus that enslaves even children in prison camps.

“It’s a flimflam,” Mr. Kelly said. “Just a show.”



The address was closely watched in South Korea, a country known for its attention to outward appearances, with a cosmetic surgery industry that is the envy of Asia. Initial reaction there was positive, at least on the substance, with a South Korean government spokesman saying, “We have already expressed our willingness to engage in a dialogue with North Korea at any time.”

In dressing up for his speech, Mr. Kim, who was educated in Swiss schools, may just be hearkening back to his grandfather, Kim Il-sung, the founder of North Korea and a man the young Mr. Kim is often said to emulate, even in his rotund frame and haircut. The grandfather was known for occasionally wearing Western-style suits, a marked contrast to other Communist revolutionary leaders of the time, like Mao Zedong and Ho Chi Minh.