A question on the actors thet go into the military

OK I noticed our actors ages 20-25 and maybe older, go into the military.
But here in the USA the people go in about ages 19- 20 and I think 20-25 is a bit old. am I missing something? being its veterans day and all, proud of the young people and their serviced in the military.

I am not too sure either but watching Korean dramas for the past years, this is what I understood.
Male Koreans can serve the military from age 19 to 30. At some point they will try to push their careers so they can come back into the entertainment industry comfortably after the national service.
The latest appointment is when they are being drafted, normally in their late twenties, but if there are some points like urgent work, they can postpone, but it’s not always granted. So sometimes they can push their military service back by some weeks or months.
The time of military service depends on where they do it, normally between 19 months (marines) and 24 months. Only because of medical reasons can they be freed of the military duties.
In the past some tried to avoid the military service, which can have a huge impact on their careers and lives, when they are found out to have faked medical histories or took other measures to stay out of it.

It’s a serious matter to attend the military for young men in Korea, because Korea has no peace agreement with the North. So, it is seen as patriotism that every man in South Korea should fulfill.

wow! thank you for that info, really good to know. so their enemy is at their back door, so to speak, and guess they have to be on their guard. very interesting… again thanks.