a korean blogger describes the situation more detail:
So... the president asks you to sing a song praising the president. The style he would prefer, if the video above is any indication, would be a terse, military march. President Park was also known to admire sentimental ballads.
Instead, you go into the studio, and write a huge, shambling, sweeping, psychedelic song that builds and builds and builds to a wild cry of passion, with lyrics like this (these aren't all the lyrics - as translated on the youtube link above):
Opening lines: Blue Sky / White clouds / A thread of wind rises / To fill my heart...
In this beautiful place, you're here and I'm here...
Hold my hand, let's go and see, run and see that wilderness...
Into this world, we were born. This beautiful place. This proud place we will live.
Today I'll go to meet you... time will pass, we will live together, then fade and fall.
Spring and summer go, Fall and winter come. (at 3:58:) Beautiful rivers and mountains!
(4:05-4:30) Your heart, my heart, You and me, Us Forever We are all, all in endless harmony.
It is a sweeping, gorgeous tribute to the beauty of Korea, and Shin's pride in his country, it contains time, seasons, mortality, harmony -- this is Shin's love of his land, with a loose, sloppy song structure, no chorus, few repeats, just a love poem sung straight through, all draped in shambling psychedelic, fuzzy, decadent rock sounds, ending with an extended musical washout as "we are all in endless harmony" disappears into the endlessness of great music.
There you go, Mr. President.
So instead of singing a tribute to the President, Shin pointedly, and passionately, sings about the beauty of the land. NOT the beauty of the government, the leader, or a vision of greatness for the people. No exhortations to respect your teacher or work hard. The rivers and mountains. He places all the politics and ambitions and dreams of the people under a giant sky of washing guitar, and sings that they will fade and fall, but the land, the beautiful land, will outlast them all.
To me, knowing the story of it, the song screams, "I love this country, Mr. President. Not you." Not only is it a pitched act of defiance, it also might be the best song he ever made.