South Korea and North Korea are still technically at war, with the 1950-53 war over the divided peninsula ending with an armistice and not a lasting peace treaty. But for a couple of hours Friday in PyeongChang, South Korea, the two nations joined to march under a unified flag at the Opening Ceremonies for the Winter Olympics. This relationship almost certainly will be fleeting, but for now it’s official, or at least social media official: As they were about to enter the stadium, the unified Koreans took a selfie.

Kim Yo Jong, younger sister of North Korean leader Kim Jong Un, took in the Opening Ceremonies in a VIP box, at one point shaking hands with South Korean President Moon Jae-in. Kim, the granddaughter of North Korean founder Kim Il Sung, is the first member of that country’s ruling family to set foot in South Korea since the war, with The Washington Post’s Anna Fifield describing her as a fitting ambassador for North Korea’s charm offensive.

The Korean athletes entered the stadium together under a unified flag showing a light blue silhouette of the Korean Peninsula over a white background. The flag has been used in such a way when the Koreas marched together at previous Olympics, but it took on more significance when unfurled at Games taking part on the peninsula itself.

U.S. skier Lindsey Vonn, for one, was impressed.

When it came time to light the Olympic flame, two members of the unified Korean women’s hockey team — Park Jong-ah from the South and Chung Su Hyon from the North — climbed stairs to jointly pass the torch to celebrated South Korean figure skater Yuna Kim, who finished the job. It was a temporary gesture at a temporary location — PyeongChang Olympic Stadium, built specifically for these Games, will be torn down when they end — but it gave the Opening Ceremonies an air of permanent hope.

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