A Korean unity flag hangs on a fence in the demilitarized zone separating the two Koreas.Kim Hong-Ji / Reuters

Editor's Note: Read all of The Atlantic’s Winter Olympics coverage.

In one of the many overtures of peace agreed upon by Seoul and Pyongyang ahead of the Pyeongchang Winter Olympics, a reunification flag took the place of the North and South Korean national flags at the opening ceremony on Friday. The symbolism of the flag, which was carried by the joint Korean delegation as it marched, is not subtle. It depicts a united Korean peninsula in a soft pastel blue against an expansive white background—a color motif that suggests peace and hope, and is most famously featured in the flag of the United Nations. At these games, the flag represents Seoul’s hope for mending long-curdled relations with the Pyongyang.

In the messy history of inter-Korean relations, the unification flag’s purpose has more or less remained the same. Debuted by the joint Korean table tennis team at the 1991 World Table Tennis Championships and subsequently unfurled at international sporting events like the 2000 Sydney Olympics and the 2007 Asian Winter Games in Changchun, China, the flag is an international affirmation of shared Korean kinship, a concept known as minjok.

The flag’s message, however, belies the heated controversy surrounding its use. It has drawn the ire of South Korean conservatives, who have criticized it for undermining South Korea’s big moment as host to the Olympics. In more colorful displays of protest, far-right conservative groups have burned it, alongside the North Korean flag and a photograph of North Korean leader Kim Jong Un. Japan, too, has joined in, though for different reasons. After Japanese officials voiced their disapproval over a version of the flag that included islands Seoul and Tokyo both lay claim to, the South Korean government eventually agreed to use an altered design that does not depict the disputed territory.

The quarrel with Japan spoke to larger questions of national identity. “In a way, [the reunification flag] is a measure that weakens South Korea’s sense of presence,” said Kim Sung Han, a former senior South Korean diplomat. “It romanticizes the current situation, based on a kind of romantic nationalism. While it’s good that we’re having North Korea participating in the Olympics and sending a cheering squad, we have to approach questions of South Korea’s national identity very cautiously.”

The concept of a unified Korea and shared nationalism, however, may already be losing purchase among the current generation of South Koreans. “The more and more we move to younger generations, the idea that we are one people is disappearing,” said Hong Woo Taek, a senior researcher at government think tank Korea Institute for National Unification.“Even in South Korea, we have our own regional conflicts, so how could we embrace North Korea as one of our own, when we haven’t even been able to resolve our own regionalism?” A recent poll by RealMeter suggested that just four out of 10 South Koreans favored the idea of the two countries flying the unification flag at the winter games—a far cry from a time when even conservatives lavished praise on its use. By contrast, a similar poll from 2002 showed that 76 percent of South Koreans approved of flying the reunification flag at the 2002 Asian Games, hosted in Busan, South Korea.

For all its associations with unity and a shared vision, however, the flag may ultimately mean completely different things for Seoul and Pyongyang. If, for South Korea, it represents a ticket to denuclearization talks, North Korea may view it as an opportunity to avoid them altogether. “The current mood is North Korea versus international society. [The flag] could shift it into the equation of the two Koreas versus international society,” said Kim Sung Han, the former diplomat. “It could create a situation where the North Korean nuclear issue is put on the back burner.” With all eyes on the Olympics, the use of the flag could also offer Pyongyang a chance for a much-needed public image makeover. “With North Korea’s repeated nuclear tests, there is an increasing number of South Koreans who perceive them as a threat,” Hong said. “In waving the unification flag, North Korea could be trying to send the message that they aren’t dangerous.”

While the narrative of a unified Korea may be co-opted more than it is genuinely embraced, one saving grace for the flag may be in the realm of sport. Despite having been separated for over 60 years, South Koreans will still root for North Korean teams when they play, waving the blue-and-white unification flag—partly because it’s the only one they can. At the 2014 Asian Games women’s soccer finals, even conservative lawmakers showed up to root for the North Korean team, which went on to defeat Japan for the gold. There is a flip side to the recent polls, too: A 2014 Korea Institute of National Unification survey asked South Koreans who they would cheer for in a hypothetical World Cup match-up between North Korea and the United States. Seven out 10 responded North Korea.

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