LINDA WERTHEIMER, HOST: This is MORNING EDITION from NPR News. I'm Linda Wertheimer.

RENEE MONTAGNE, HOST: And I'm Renee Montagne. South Korea may have put frontline troops on alert after the death of North Korea's Dear Leader, but the president of South Korea is assuring the North that his country is not hostile.

And in North Korea, the state-run media has been bolstering the late leader's son and successor, Kim Jong Un, calling him an outstanding leader. With the end of the Kim Jong Il era, North Korea's neighbors are re-calibrating their policies and weighing new security concerns.

NPR's Louisa Lim starts her report on a press tour of the demilitarized zone - the DMZ - between North and South Korea.

UNIDENTIFIED MAN #1: If any trouble were to break out it, could very well happen here. It has in the past...

LOUISA LIM, BYLINE: It's been called the world's most dangerous border. But as American soldiers herded the press pack around the DMZ, the biggest danger appeared to be the weather.

UNIDENTIFIED MAN #2: Has it been really cold up here?

UNIDENTIFIED MAN #3: Oh it's been hell...

(SOUNDBITE OF LAUGHTER)

LIM: At the border, half a dozen South Korean soldiers stood at the alert, facing off against one solitary North Korean soldier in khaki. The only unusual sign was the North Korean flag flying at half-mast.

Despite the political shock of Kim Jong Il's sudden death, the military situation in the DMZ is unchanged, according to the spokesman for U.S. Forces in Korea, Colonel Jonathan Withington.

COLONEL JONATHAN WITHINGTON: All is calm.

LIM: Completely as normal?

WITHINGTON: Yeah.

LIM: Have you seen any changes?

WITHINGTON: Normal operating - we're operating under normal armistice conditions. We've no seen no unusual movements or activities.

PRESIDENT LEE MYUNG-BAK: (Foreign language spoken)

LIM: South Korea's conservative President Lee Myung-bak urged stability in the North. He underlined that Seoul does not feel animosity towards Pyongyang and said there was room for flexibility in ties. These words seem to indicate a softening of stance, the emergence of a new policy towards the North.

JASPER KIM: I think South Korea, its policy is being reconstituted as we speak, and so is the world in terms of how to deal with this very unusual state.

LIM: Jasper Kim is the author of a book about South Korea and a visiting scholar at Harvard. He describes Seoul's policy to Pyongyang as being in flux and in a state of slight confusion.

KIM: What he's trying to do - the South Korean president - is trying to get closer to North Korea, but not exactly close. So this is a little bit in stark contrast to what his policy was in the beginning of his administration, that North Korea is a state that is not a friend to South Korea.