Abstract
For millennia China's enemies have come chiefly out of northern and central Asia. In the 1980s, after a historically anomalous century during which most of her enemies came from the sea, China's defences once again are orientated north and west. The military threat of the 1980s is more complex than that posed by the barbarian nomads of old. The Soviet armed forces can launch land-air battles simultaneously all along the 10,000-kilometre Sino-Soviet border. Moreover, time and space factors which long shielded the interior of China provide little protection in the missile age.