The Livre noir goes on to say that

The conflict on the question of the political line was very bitter. But the Cambodian delegation preserved its calm and did nothing to annoy ... the Vietnamese. After the departure of Secretary Pol Pot for Kampuchea, the Vietnamese knew that the Communist Party of Kampuchea would maintain its line which was to carry out armed struggle in combination with political struggle.12

The Livre noir is a mélange of truth, reconstructed history, and wishful thinking. The imposition of a Vietnamese-language text on the Khmer, Le Duan’s hectoring, and the Khmer’s unwillingness to annoy the Vietnamese sound plausible, but assertions that there was an open “conflict” with Vietnam and that Sar pursued an independent line or that he raised the idea of independence during his visit are contradictory. The Communists’ decision to combine armed and political struggle was not taken until late 1967, and no action flowed from the decision until January 1968. In the Livre noir, Saloth Sar probably presented the thoughts he had had at the time, but these were heated in retrospect by Vietnam’s behavior and his resentment at having been unable to speak out.

The sessions with Le Duan were humiliating to Sar, and there is a poignancy to his bravado twelve years later. His views as the leader of a sovereign party were not solicited or treated with respect by the Vietnamese. He was required to give the same acquiescence that Sihanouk demanded of Lon Nol or that the Vietnamese demanded of their protégé Heng Samrin after 1979. Had Saloth Sar responded as stubbornly as he said he did, the Vietnamese would have found someone else to lead the Cambodian Communist party. They would not have allowed him to visit China. Because he did go to China, and returned home as the party’s leader, we can assume that he swallowed his pride and by his silence seemed to accept Vietnamese advice.

The Visit to China

Sometime during his visit to Vietnam, Sar made it known that he wanted to go to China, at that point a strong ally of Vietnam in its war with the United States. Permission from Beijing took several months to arrive. Sar probably filled his time with political and military training (and perhaps language study), which neither he nor the Vietnamese would have been eager to point out after 1977.

The amount of time he spent in China is uncertain. He never mentioned the trip in public. Sources that mention the visit date from 1978 or later and are mostly Vietnamese. These sources, in turn, paint Saloth Sar as having been mesmerized by the “Gang of Four,” a group of high-ranking radical Maoists who enjoyed a spectacular spell of power in the 1970s and were imprisoned soon after Mao’s death in 1976. These postdated Vietnamese accusations are probably spurious, although a former Chinese diplomat, speaking on condition of anonymity, stated in 1997 that during his 1966 visit Saloth Sar had been befriended by K‘ang Sheng, a senior Communist cadre who had often served at the head of Mao’s secret police. Since his return from the Soviet Union in 1937, Sheng had earned a reputation for deviousness and for presiding over several ruthless, far-reaching purges. In 1965, one of his duties was to greet visitors to China from friendly and in many cases clandestine Communist parties. Although no record of his conversations with Saloth Sar has survived, it seems likely that Sheng praised the radicalism of Sar’s revolutionary stance and pointed out to him the importance of locating and rooting out internal enemies.