While North Korea remains deeply impoverished, estimates of annual growth under Mr. Kim’s rule range from 1 percent to 5 percent, comparable to some fast-growing economies unencumbered by sanctions.
But a limited embrace of market forces in what is supposed to be a classless society also is a gamble for Mr. Kim, who in 2013 made economic growth a top policy goal on par with the development of a nuclear arsenal.
Mr. Kim, 33, has promised his long-suffering people that they will never have to “tighten their belts” again. But as he allows private enterprise to expand, he undermines the government’s central argument of socialist superiority over South Korea’s capitalist system.
There are already signs that market forces are weakening the government’s grip on society. Information is seeping in along with foreign goods, eroding the cult of personality surrounding Mr. Kim and his family. And as people support themselves and get what they need outside the state economy, they are less beholden to the authorities.
“Our attitude toward the government was this: If you can’t feed us, leave us alone so we can make a living through the market,” said Kim Jin-hee, who fled North Korea in 2014 and, like others interviewed for this article, uses a new name in the South to protect relatives she left behind.
After the government tried to clamp down on markets in 2009, she recalled, “I lost what little loyalty I had for the regime.”
Kim Jin-hee’s loyalty was first tested in the 1990s, when a famine caused by floods, drought and the loss of Soviet aid gripped North Korea. The government stopped providing food rations, and as many as two million people died.
Ms. Kim did what many others did to survive. She stopped showing up for her state job, at a machine-tool factory in the mining town…