This is the fourth of five interviews with prominent US scholars on an upcoming South Korea-US summit and the alliance. -- Ed.

Despite their differences over North Korea and a US missile shield, Presidents Moon Jae-in and Donald Trump need to avoid an “open clash of wills” when they meet this week, which may aggravate nuclear issues and future cooperation, a leading US expert said.

David Straub, the Sejong-LS Fellow at the Sejong Institute in Seoul who served at the US State Department for 30 years, offered a grim outlook for the two leaders’ first summit, slated for June 29-30 in Washington. He pointed out Moon’s pursuit to restart dialogue with Pyongyang, which has little appeal for Trump who has settled on policy calling for “maximum pressure and engagement.”

“The Trump administration wants a negotiated settlement but believes that returning to talks now, when the North Koreans have stated clearly and firmly they are not even willing to negotiate about denuclearization, would be worse than meaningless,” Straub said told The Korea Herald via email.

“It will be very difficult for the two presidents to completely bridge this gap. To the extent they can‘t, it will be good if they can at least paper over the differences, rather than have an open clash of wills. That would help neither administration and would only make the North Korea problem worse.”

On June 15, Moon said if Pyongyang halts its nuclear and missile tests, he would pursue talks, including parallel negotiations on denuclearization and a peace treaty, as well as the normalization of North Korea-US relations.

With the North remaining steadfast in its nuclear ambitions, the Trump administration is unlikely to seek a freeze deal, which Straub said would be deemed as Washington’s de facto acceptance of Pyongyang as a nuclear state.

“Even under such a freeze, which could never be fully verified, North Korea would continue significant nuclear and missile development work. And it could break the freeze whenever it wanted,” he said.

“In the meantime, the US’ effort to apply ‘maximum pressure’ on North Korea to change its strategic calculus and decide to engage in genuine denuclearization negotiations would be greatly undermined within the international community.”

The retired longtime diplomat expressed criticism in particular over Cheong Wa Dae’s suspension of the deployment of the US’ Terminal High Altitude Area Defense system here, over which Trump may ”very well press“ Moon at their summit.

Another damper for the meeting was the tragic death of Otto Warmbier, an American college student who was detained in the North for 1 1/2 years. Straub said the case would make it “even less likely” for Washington to resume dialogue or make concessions unless the Kim Jong-un regime clearly signals a willingness toward genuine denuclearization negotiations,

“Not only Trump but much of the American foreign policy establishment has been shocked, perplexed, and upset by the Moon administration’s attitude toward THAAD, ... The Moon administration‘s current ambiguous position is winning it no friends in Washington or Beijing,” he said.

”There is great anger in Washington and among Americans generally about what North Korea did to Otto Warmbier. ... The situation is very serious, and it will be even worse if North Korea does not immediately release the remaining three hostages."

By Shin Hyon-hee (heeshin@heraldcorp.com)