Asia arms race harms both growing giants

India's militarisation has often had its sights set on Pakistan since partition in 1947. Many in New Delhi may view their former compatriots as an existential threat, but India has built a serious economic and military advantage over its old rival. The successful launch on Wednesday of the Agni-V missile, capable of carrying a nuclear warhead with a range of 5,000 kilometres, was instead a shot across the bows of Beijing.

Taken alone, this test could be little more than a milestone for an aspiring global player - a previous incarnation of the Agni programme was known as the "technological demonstrator". But coming after provocative military manoeuvres from both sides in recent months - from joint Chinese-Pakistani military exercises to Indian war games on China's border - it's worth reminding both New Delhi and Beijing that they have more to gain through cooperation than by increasing competition.

In many ways, Asia's two giants are closer than ever. Both economies are booming, and President Hu Jintao's visit last month to New Delhi was a reminder that, above all, economic opportunity can trump antagonism.

And yet, India and China have an uneasy friendship, having already spilt blood in the 1962 Sino-Indian War. Disputes along the Himalayan border have never been settled, and both sides maintain competing claims to areas larger than Switzerland. Beijing, meanwhile, has stationed missile silos on India's northern border.

Given these threats, New Delhi's efforts to challenge China's military dominance is understandable. They are, however, ultimately unhelpful. Neither giant needs an arms race - which is where the continent seems to be heading. We have already seen spillover from China's military assertiveness in the South China Sea. As Beijing defends its claims to disputed territories, and looks to extend its influence, South-east Asian states are stockpiling their own arsenals.

India and China have dramatic differences in their political models (the world's largest democracy and the single-party state). But they share economic and development ambitions that need not be mutually exclusive.

A new era of weapons technology capable of levelling Shanghai might be the logic of geopolitics; perhaps that era is inevitable. Ultimately, though, it will be the investments both sides make in cooperation that will have the best chance of redefining the Asia of tomorrow.