Third Front Construction

By the early 1960s, the collapse of the Sino-Soviet alliance and the concentration of China's heavy industry in vulnerable coastal cities left Beijing anxious about a surprise attack — a concern sharpened by the country's push to build a nuclear arsenal, whose facilities Zhou Enlai proposed relocating for security in a January 31, 1964 report to the Central Committee. Deepening American involvement in Vietnam, and the Gulf of Tonkin incident that August, hardened the sense that a coastal China faced a real prospect of war.

At a central work conference on the Third Five-Year Plan on May 15, 1964, Mao Zedong pressed for accelerated construction of an industrial base at Panzhihua in Sichuan. Twelve days later, chairing an enlarged Politburo Standing Committee meeting on May 27, he laid out a three-tier industrial geography — coastal China as the "first line," the central provinces as the "second line," and the mountainous southwest and northwest interior as the "third line" — describing agriculture and defense industry as the nation's "fists" and basic industry as its "seat," warning that "for the fists to strike hard, the seat must sit firm." The next day, May 28, he told central bureau leaders: "If Panzhihua doesn't get built, I won't be able to sleep — we must be resolved to build it," insisting the third line needed not just railways but steel, coal, machinery, chemicals, and military industry all together.

The Gulf of Tonkin incident on August 2 pushed the leadership to reorient the entire Third Five-Year Plan around war preparedness rather than consumer needs. On August 17, meeting at Beidaihe, Mao pressed for urgent construction of the Chengdu–Kunming, Sichuan–Guizhou, and Yunnan–Guizhou railways; two days later, Li Fuchun, Bo Yibo, and Luo Ruiqing jointly submitted a report titled "On How Economic Construction Should Guard Against Sudden Enemy Attack," recommending that future industrial investment be concentrated in the third-line interior. The Central Committee began setting up construction agencies that September, and by September 14, 1965, had made third-line construction the central task of the Third Five-Year Plan.

The Panzhihua Iron and Steel Complex and the Chengdu–Kunming Railway became the program's flagship projects, alongside the secretive Xichang Satellite Launch Center and hundreds of coded military-industrial plants scattered through mountain valleys across thirteen provinces and regions. In November 1965, Marshal Peng Dehuai — six years after his purge at the 1959 Lushan Conference — was appointed third deputy director of the Southwest Third Front Construction Commission, where he proposed a "one point, one line, one zone" plan centered on the Panzhihua steel plant, the Chengdu–Kunming Railway, and a conventional-weapons industrial base around Chongqing. Between 1964 and 1980, the state invested roughly 205.26 billion yuan — 39 percent of national capital construction spending in those years — building more than 1,100 large and medium-sized enterprises and relocating several million workers, cadres, intellectuals, and soldiers to the interior.

Sited under the military doctrine of "relying on mountains, dispersed, and concealed," and built under a "three simultaneous" approach that pushed design, construction, and production forward all at once, many plants ended up isolated, difficult to supply, and, once the war threat receded, hard to sustain economically. For the workers and families who relocated — often with little notice and under strict secrecy — the human cost endured across generations, summed up in a phrase that circulated among third-line communities: "we gave our youth, then our whole lives, and after our lives, our children too." Beginning in November 1980 the state moved to scale back the least viable small third-line military plants, and on December 3, 1983 the State Council established a leading group to guide the program's adjustment and conversion to civilian production — a process that unfolded gradually through the 1980s.