Analysts said they doubted that new sanctions would make any real difference on the already heavily penalized country. If anything, they said, the designation will make diplomacy more difficult without increasing Washington’s leverage, warning that North Korea will probably take the naming and shaming as another reason to stick to its hard-line policy of developing and testing nuclear weapons and intercontinental ballistic missiles.

“It’s hard to see any real impact on North Korea, which has lived through all manners of sanctions for seven decades,” said Paik Hak-soon, a senior analyst at the Sejong Institute, a South Korean research organization. “What it does instead is to send a clear message to North Korea that Trump is not interested in talks, another sign and reconfirmation that the Americans remain a hostile force.”…

Mr. Trump’s announcement gives the country an excuse to justify a new weapons test and “deflect blame onto the U.S.,” said Lee Sung-yoon, a Korea expert at the Fletcher School of Law and Diplomacy at Tufts University in the Boston area.