Why does the TV series Descendants of the Sun say unity?

As far as I know, unity is a slogan of the Korean army. Before that, there was unity, loyalty and self-confidence, which was similar to the slogan or code word in our army, and the salute was the same as our heads. A soldier and a doctor among the descendants of the sun were protected and guarded at this moment. Even if they are sad when they leave or cry for joy when they meet, they must turn around and continue to complete their respective missions, putting the great love of the country above the love between men and women. Everyone firmly believes in their own beliefs and melts every little love into great love together. Such words are needed to stimulate motivation and enhance attraction.