Time Out says
The most expensive Korean movie ever made (US$13 million), and the most successful (11 million admissions and counting), Kang's third feature reruns the Korean War as a family melodrama. It's named after Korea's national flag. One day in 1950 shoeshine boy Jin-Tae (Jang) is pressganged into the army alongside his intellectual kid brother Jin-Seok (Won). Determined to find a way to send Jin-Seok home to mum and university, Jin-Tae keeps risking his life for a gong. However, Jin-Seok is appalled to see him brutalised by his apparent lust for glory and disowns him. Then, when Jin-Tae hears (wrongly) that Jin-Seok has been burned alive by zealous homeguards, he furiously defects to the communists and becomes a feared military commander. The film's unrelenting audio-visual assault is somewhat at odds with its 'strong men cry' sentimentality; this is not the Korean Saving Private Ryan it would like to be. Most non-Koreans, furthermore, are likely to baulk at Jang's bug-eyed, hysterical performance, the ropey CGI animation and the amateurish subtitles.