North and South Korea share a peninsula and half a name, but they could not be more different in their approach to faith, according to international religious freedom experts.
The North Korean regime outlaws nearly all forms of religious practice, sending citizens caught practicing Christianity to political prison camps.
"North Korea has one of the worst records in the world as a repressive abuser of all human rights," said Tina Mufford, senior policy analyst for the United States Commission on International Religious Freedom.
South Korea, on the other hand, allows faith groups to flourish. It scored better than the United States on Pew Research Center's latest index of government restrictions and social hostilities.
"The government is very careful not to take any sides in terms of religion" and to encourage and provide space for everyone, said Brian Grim, president of the Religious Freedom & Business Foundation.
Comparing the two countries highlights the value of robust religious freedom protections, experts said. As North Korean leaders struggle to keep their citizens fed, South Korea enjoys the humanitarian contributions of people of faith.
"That is one of the great costs of religious intolerance: it drives away religious people who have a desire to contribute to society," Grim said.
North Korea's and South Korea's religion-related policies stem from the political systems in place. South Korea is a democratic state, while North Korea is led by a powerful dynasty that demands citizens' complete devotion.
"The North Korean regime is really unlike any other in the world," Mufford said. "You're not allowed to believe in anyone or anything else than the Kim family."
Christianity is particularly problematic in this environment because of its association with Western culture, she added. Even just crossing paths with a Christian missionary during a trip abroad could lead to imprisonment.
North Korean law prohibits religious activity outside of state-controlled houses of worship, and activities within these spaces are closely monitored. Worship within the country's sanctioned Protestant, Catholic and Russian Orthodox churches would be very foreign to people who practice these faiths elsewhere in the world, experts said.
"It's a church with no pastors," said Grim of North Korea's one Catholic Church.
The U.S. Commission on International Religious Freedom has designated North Korea as a "country of particular concern" since 2001, arguing that believers within the country essentially have no legal way to fully express their faith.
"Those who follow a religion or other form of belief do so at great risk and typically in secret, at times even keeping their faith hidden from their own families," commissioners wrote in the group's 2017 annual report.
Across the border, religious groups have the opportunity to not only build churches and worship in the open, but also to organize schools or humanitarian organizations. Some of the largest universities in South Korea are faith-based, Grim noted.
"By various measures, South Korea has one of the best approaches to religious freedom in the world," he said.
Protestant Christianity, Catholicism and other Christian denominations have thrived in South Korea since the turn of the 20th century without crowding out a variety of indigenous faiths.
"In the early 21st century, 20,000 South Korean missionaries were working in more than 170 other countries around the world, making Korea second only to the United States as a Protestant missionary hub," wrote Alec Ryrie in "Protestants: The Faith That Made the Modern World."
In spite of its egregious treatment of its own citizens, North Korea is most often talked about in the context of the threat it poses to other countries, Mufford said. Few outsiders have a strong understanding of what happens inside the country's borders, because leaders tightly control access.
Human rights organizations and religious freedom researchers continue to work to expose conditions inside North Korea, but their efforts rarely earn the attention given to the latest nuclear-arsenal news. Mufford hopes people's awareness about the difference between the two Koreas will increase while the region is in the Olympics spotlight.
"We need to address the human rights issues in North Korea. It can't just be about the nuclear issue all the time," she said.
The Olympics already led to one valuable breakthrough, prompting the first high-level talks between North and South Korea in two years. North Korea agreed to send officials and athletes to the games, which begin this week.
"That's a tremendous step forward," Grim said.
South Korean faith communities will be watching ongoing negotiations closely, as they seek to serve people in need in the north. In 2011, a group of religious leaders from the south traveled to North Korea to encourage reconciliation, but most observers thought North Korean leaders were only interested in humanitarian aid.
Many South Korean faith groups have direct ties to North Korea's more religious past and feel invested in efforts to improve religious freedom policies there, Grim noted.
"Many older religious leaders in South Korea were actually born in North Korea and some may be children of the people who fled," he said.