The Heavy-Chemical Industry Drive (usually shortened to "HCI") was an economic development plan enacted in the 1970s under the regime of South Korean dictator Park Chung Hee.
The dirigisme policies instated by Park—nationalization of the country's banking system, and directing cheap credit to the export sector—had produced rapid development in the textiles and apparel industries.
However, the country lacked any sort of heavy industry, and was dependent upon the United States for many raw materials and capital goods during the early years.
On the other side of the DMZ, North Korea had amassed an enormous army, and an industrial establishment almost wholly devoted to the supply of its armed forces.
Being already the country's largest firms, they were decided best positioned to undertake the massive capital investment necessary to establish a heavy industrial sector (Park was uninterested in breaking up their power or putting their resources under a different form of control).