Besides supplying large amounts of military aid and training from 1950, Chinese advisors also introduced wave tactics to the General Staff of the Democratic Republic of Vietnam in a bid to overwhelm the French positions, as the Chinese army had done against the Republic of China during the Chinese civil war and was trying to do against the Americans in the Korean War. However, such human wave tactics were extremely risky when applied in Vietnam. For one, the French Expeditionary Corps was a professional army superior to Chiang Kai-shek’s armed forces, and both Generals Vo Nguyen Giap and Chen Geng conceded that the French were no pushover. Though France’s Air Force in Indochina had serious problems, it was more modern and effective than the Chinese republican one had been. Not only did the French have more advanced artillery, they were also good at using it in complex and coordinated ways and at night. Moreover, compared to China and its armies, the Vietnamese population was so much smaller that it could not support such costly wave tactics without risking the depletion of a relatively small army (around 250,000 in the early 1950s, including 115,000 regular troops). In short, the Vietnamese were applying a Chinese military model against a superior enemy equipped with modern firepower, in different Vietnamese circumstances, in a much smaller country, and at an increasingly important international conjuncture that obliged them to score a big victory against the French at Dien Bien Phu. Wave tactics showed their limits in the Vietnamese battles in the Red River Delta in 1951 and even in the uplands. The bloody Vietnamese failure to take Vinh Yen was a painful case in point; Na San was an equally costly defeat in 1953. And the tactics used in the battle of Dien Bien Phu had much more in common with the trench warfare used at Verdun than the wave tactics the Chinese deployed in Korea. See also AID, CHINESE COMMUNIST.