Should China-India relations deteriorate to the verge of military confrontation and the riots in Tibet spread extensively, the first combat units of the Chinese People's Liberation Army to be called to action would be the No. 52 and No. 53 Mountain Brigades under the Tibet Military Region.

The No. 52 Brigade, stationed at Linzhi, is highly mechanized and armed with T-92 wheeled armored vehicles and HJ-8/9 anti-tank missiles. National highway 318 directly connects Linzhi and Lhasa; thus it is logical to conclude that the T-92 wheeled armored vehicles on the streets of Lhasa were from this brigade. The No. 52 Mountain Brigade is stationed at Milin and is also the PLA's combat unit stationed closest to the city of Lhasa.

National highway 318 is in fact the southern route of the Sichuan-Tibet highway. In the event of war or future large-scale riots in Tibet, the highway will be the key passageway for combat troops from the Chengdu Military Region to enter Tibet.

However, this key highway runs across the Minjiang and Daduhe rivers in a region with an average altitude of 14,000 feet above sea level, and thus is very susceptible to attack by the Indian air force or assault by organized rioters. Most of the highways within the Tibet region will be within striking range of the Sukhoi Su-30MKI fighters soon to be deployed in the No. 30 Squadron of the Indian air force at Tezpur.

If the T-90/89 armored personnel carriers used in Lhasa were indeed from the PLA's 149th Mechanized Rapid Reaction Division of the Chengdu Military Region, they were most likely transported first from Chongqing to Xining, then to Golmud to connect to the Qinghai-Tibet railway and continue on to Lhasa. The whole journey would take about 48 hours.

Such troop movements would be much faster and cheaper than before. Calculated on the basis of being able to transport most of the heavy equipment of a whole mechanized division within 48 hours -- it is unlikely that all the division's equipment would be moved -- the People's Liberation Army would be able to transport approximately 10 light mechanized divisions and some heavy mechanized divisions through the railroad to Tibet from the Lanzhou and Chengdu Military Regions within 30 days.

Of course, should there be a military conflict between China and India, the Qinghai-Tibet railway would be a prime target for airstrikes by the Sukhoi Su-30MKI fighters of the Indian air force's No. 30 Fighter Squadron, the MiG-27 fighters of the No. 22 Squadron at Hashimara and the "Jaguar" attackers of the Indian air force's No. 5 Squadron at Ambala.

The only obstacle to this mass movement of regular armed troops and equipment would be the capacity of the Qinghai-Tibet railway and the number of available trains. China once claimed that the annual transport capacity of the railway was 5 million tons, an average of 13,888 tons per day.

-- Next: China's rail and road systems to hold Tibet

(Andrei Chang is editor in chief of Kanwa Defense Review Monthly, registered in Toronto.)