Former U.S. diplomat Christopher Hill says North Korea's heir apparent, Kim Jong Un, isn't ready to lead the nation.

"He is truly not a primetime player, ready for primetime play," Hill said. "This is someone who looks very diffident, very shy."

"He's not particularly prepossessing, and frankly has very little experience in this regard," he added. "The Chinese themselves are a little worried about whether he's really up to the task of running the country."

Hill, who served as ambassador to South Korea and participated in nuclear negotiations with the North, said it could take years to get Kim Jong Un up to speed.

In the meantime, the military -- and even other members of his family -- could engage in a power struggle.

But evangelist Franklin Graham says Kim Jong Il's death could provide a breakthrough in U.S. relations with North Korea.

Graham's Samaritan's Purse ministry is on good terms with the North Korean government.

This year, the relief group built hospital facilities and shipped food and other agricultural aid to the isolated nation.

Graham said President Obama can help North Korea's heir-apparent by sending desperately needed food for the millions of the country's malnourished citizens.

He suggested the aid could help ease tensions with the United States and the harsh persecution of North Korea's Christians.    

Meanwhile, the deceased leader Kim Jong Il is lying in state Tuesday. His son, Kim Jong Un, and other leaders have paid their respects.

Thousands of North Koreans will have the opportunity to view his body before the state funeral on Dec. 28.