For the most skilled and toughest North Korean negotiator, the task of pushing the line while remaining on cordial terms with the man across the table carries inherent risks. A change in policy may be fatal. One mistake, and you may never live to make another.
Take Kim Kye-Gwan, the North Korean vice foreign minister with whom Christopher Hill spent years cozying up to when Hill was US nuclear envoy and assistant Secretary of State for Asia and the Pacific. Kim got Hill to sign on to two deals in 2007 under which North Korea agreed in careful detail first to disable and then dismantle its entire nuclear program. All the US had to do was remove North Korea from its list of state sponsors of terrorism - something former president George W Bush was glad to do in his waning months in office.
So what is Kim's reward for all his success in bamboozling the Americans into thinking they had succeeded in getting North Korea to give up its nukes? He seems to have disappeared, and nobody has a clue as to whether he's dead or alive, working on a chicken farm or sent to a prison for re-education. Analysts here believe Kim may have become a scapegoat for hardliners in the ascendancy in North Korea.
Bruce Bechtol, professor at the Marine Corps Command and Staff College in Quantico, Virginia, says the purges have accompanied a shift in the political winds. An example is that of Choe Sung-chol, who as vice chairman of the Asia-Pacific Peace Committee was responsible for dealing with South Korea. He was reportedly "languishing on a chicken farm" in January while undergoing "revolutionary training" - before he was reported executed.
Choe committed the grave offense of making "wrong predictions" about the policy of Roh's conservative successor, Lee Myung-bak, elected president by a landslide two-and-a-half months after the summit.
Among the first in the line of fire, beside negotiators all too visibly involved in dealings with the US and South Korea, have been those attempting to escape across the Yalu and Tumen river borders to China.
One experienced source for that perception is Tim Peters, director of Helping Hands Korea which has years of experience aiding escapees. "The penalties are getting stronger," Peters has been quoted as saying. The government is even refusing to issue passports to those who need to go to China and elsewhere on normal business.