An article by Josh Chin, writing in the The San Francisco Chronicle states:
An avowed agnostic raised in the smug spiritual certainty of Mormon Utah, I've always been deeply skeptical of missionaries.
Watching Grace, a North Korean refugee in China [as she explained that she planned to risk her life to return to North Korea “to spread the Gospel], I felt the bile rise in my throat. This, I thought, was evangelical exploitation of the first order, spiritual blackmail masquerading as liberation.
Likening the North Korean Underground Railroad to the original felt like an unconscionable lie -- a PR formulation meant to reassure rich American donors -- and I immediately began to map out the contours of a story that would pierce the facade.
Soon enough, doubts started seeping in. Where the Antebellum South had its slave hunters and lynch mobs, northeast China has a cadre of border guards and secret police tasked with returning illegal North Koreans to their homeland and arresting the people who help them.
Like the early American abolitionists, the [North Korean Underground Railroad] had been doing what no other group possessed the courage to do, and, like the abolitionists, sought no recognition for what they did. They earned no payoff other than a sense of being true to their beliefs.
What motivates people to sacrifice themselves like this? What keeps them from running back to the safety of the day job, the leisurely weekend, the phone line that doesn't click suspiciously?
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