What concerns American, South Korean and Japanese analysts, however, is not simply the presence of the hard-to-detect gas but its source.
And by the time conventional American reinforcements arrived, some South Korean military analysts say, the war would be over.
"Their ground forces can come down any one of eight possible north-south corridors, and until they reach a certain point, we will not know which one," a South Korean military analyst said.
Dae Soo Min (Doris)- A female Korean analyst brought in to help aid Jack.
South Korean analysts noted North Korea's history of trying to drive a wedge between South Korea and the United States.
Some South Korean analysts said the confluence of discussions about the nuclear issue held out hope that the talks would be revived, though few expect them to make much progress soon.
He took over as party president last month, but, according to foreign diplomats and Korean analysts, he has not yet grabbed the reins firmly.
American and Korean analysts cite many reasons why the people of Korea are increasingly willing to criticize the United States.
Worrisome as North Korea's nuclear potential is, Japanese, South Korean and American analysts say they are even more worried by the Kim Government's unpredictability.
Some South Korean analysts estimate that at least 10,000 North Korean refugees are hiding illegally in neighboring China.