The Wikipedia article on Hangul states that
Beginning in the 1970s, hanja began to experience a gradual decline in commercial or unofficial writing in the South due to government intervention...
If true, what form did this intervention take?
Korean Language Stack Exchange is a question and answer site for linguists, teachers and students of the Korean language. It only takes a minute to sign up.Sign up to join this community
Just as I guessed, a big factor was (not teaching Hanja in) the schools...
South Korean primary schools abandoned the teaching of hanja in 1971. It is taught in separate courses in South Korean high schools, separately from the normal Korean-language curriculum. Formal hanja education begins in grade 7 (junior high school) and continues until graduation from senior high school in grade 12. A total of 1,800 hanja are taught: 900 for junior high, and 900 for senior high (starting in grade 10). Post-secondary hanja education continues in some liberal-arts universities. [ . . . ] .......
Debate flared again in 2013 after a move by South Korean authorities to encourage primary and secondary schools to offer hanja classes. Officials said that learning Chinese characters could enhance students' Korean-language proficiency; protesters called the program "old-fashioned and unnecessary".
Two other forms of "government intervention" I can imagine are:
Revising guidelines so that fewer Chinese characters are used in govt documents
Less and less emphasis on Hanja in examinations related to govt jobs, and public certifications (lawyers, doctors, diplomats, teachers, police, civil service, public servants, ...).
Yes. In order to boost nationalism Park Chung Hee literally banned hanja from school and publications in the 70s, hence from that generation until now nobody knows hanja and do not want to learn it. Koreans like to say that they stopped using hanja naturally, but they are ignorant of their own recent history or do not want to acknowledge it. They were just forced to forget hanja. It's an example of how a government can make its people more stupid and ignorant. Not knowing hanja means that all the documments and books written before the 60s cannot be read at ease anymore, making the people even more ignorant about their history.