Pakistan Defence

It's very hard to say worth it or not. Russian Empire took China millions square kilometers land in Tsarist Russia era, Soviet helped us in 1950s. But when Soviet wanted China to follow him like west Europe in 1960s, Mao said big NO.

Our northern border is wide open, not much mountains. It's very hard to resist Russia pressure in 1960s when China has no nukes. Mao do not want to be a vassal state in any kind, we paid very high price to confront both super power in the same time. China almost rebuilt all the industry in south west(mountainous region) of China to resist Soviet military pressure. It's trillion dollar project nowadays.