WASHINGTON – A former Defense Department official who focused on North Korea for more than 30 years said Tuesday that reforms within the totalitarian state will remain challenging until the totalitarian nation’s internal power system changes.

Robert Collins, now a senior adviser to the Committee for Human Rights in North Korea, wrote a study that spurred a panel discussion at the American Enterprise Institute. One panelist called Collins’ work a landmark report on the North Korean regime’s mysterious operations.

Collins, who has lived in South Korea for most of his career, has continued to research and write about the country since retiring.

The North Korean government, Collins said, is run by an inner circle of party officials, who act as “puppet masters” of government officials in Pyongyang.

“When we talk to a North Korean diplomat, we are not talking to someone who makes decisions,” he said. “They’re being manipulated.”

The system under President Kim Jong-un, he said, essentially works on loyalty, with government employees gaining more power and benefits as they demonstrate greater commitment to the Communist Party. Conversely, younger party officials rarely critique Kim for fear of losing their jobs—or worse.

Their fears are not unfounded: In December 2013, North Korean state media announced that Kim ordered the execution of his own uncle. (State media claimed he was killed for “half-heartedly clapping.” The Washington Post wrote at the time that it was more likely Kim was asserting himself as a new leader.)

The culture of loyalty has become so entrenched, and the benefits for those who follow Kim’s orders so great—the young leader has built waterparks for party officials, Collins said—that curbing the regime’s human rights abuses seems near-impossible.

“The concept that there could be any reform in North Korea is on the verge of being ludicrous,” he said.

The New York Times reported that North Korea’s rocket launch on Sunday is part of a program to develop an intercontinental ballistic missile. The launch followed the country’s claim in January that it detonated a hydrogen bomb. Experts have since raised doubts about that claim.

David Maxwell, a retired Army colonel who teaches at Georgetown University, said U.S. officials should use Collins’ report to understand the Kim regime better.

“If I were going to negotiate with the regime … I would consult this report, in order to understand how it works and who makes the decisions,” he said. “This report is more than an academic exercise. It is practical and valuable information.”