It has taken America’s leaders a long time to learn the lessons of nuclear weapons. President Harry Truman, who took the decision to bomb Hiroshima and Nagasaki called the atomic bomb the “greatest thing in history.” Almost 20 years later, with America having lost its nuclear monopoly, trapped in a desperate growing arms race with the Soviet Union, and having survived a crisis that threatened nuclear war, President John F. Kennedy described the bomb as having turned the world into a prison in which man awaits his execution. Fast forward another two decades, under pressure from peace movements, President Ronald Reagan agreed with Soviet leader Mikhail Gorbachev that the superpowers should eliminate all nuclear weapons.

It’s not all politics and public relations. Even the hardest of the old cold warriors have now started to talk of the urgent need to abolish nuclear weapons. They recognize them as perhaps the greatest threat to American power today. In January 2007, former secretaries of state George Shultz and Henry Kissinger, former secretary of defense William Perry, and former chairman of the Senate Armed Services Committee Sam Nunn embraced “the goal of a world free of nuclear weapons.” This vision was endorsed in 2008 by former secretaries of state and defense and others, both Republican and Democrat, including Madeleine Albright, James Baker, Zbigniew Brzezinski, Warren Christopher, Colin Powell and Robert McNamara. But, once again, there has been no change in policy.

While America’s leaders have started to understand that the search for nuclear security is a costly and dangerous pursuit that will take on a life of its own, knows no end, and brings grave new dangers, this hard-won recognition has still not come to South Asia. In the ten years since the May 1998 nuclear weapons tests by India and Pakistan, the nuclear logic continues to unfold there relentlessly.

Both the Indian and Pakistani governments sold the nuclear tests to their publics as guaranteeing national security. The Kargil war followed barely a year after the tests. The war proved that the bomb could not defend India from attack and was no guarantee of victory for Pakistan. It showed that two nuclear armed countries can fight a war and that in such a situation leaders in both countries will threaten to use nuclear weapons. It should have soon been clear that the bomb was no defense.

But Kargil was not enough to teach caution and restraint. A little over two years later, India and Pakistan prepared to fight again. An estimated half a million troops were rushed to the border, and nuclear threats were made with abandon.

What lessons have been learned? None, other than they needed to be better prepared to fight a war. Both countries have carried out major war games that assumed the possible use of nuclear weapons.

India and Pakistan are still producing the plutonium and highly enriched uranium that are the key ingredients in nuclear weapons. Nuclear policy makers in both countries obviously do not think they have enough weapons. They have never explained how many cities they seek to be able to destroy.

For the past decade the two countries have also been waging a nuclear missile race. Some of the tests are user trials and field exercises by the military. They are practicing for fighting nuclear war.

Like their peers in other nuclear armed states, leaders and military planners in India and Pakistan seem impervious to the effects of the kind of war that they plan and prepare for. A war in which India and Pakistan each use only five of their nuclear weapons on the other’s cities could kill several million people and injure many.

The effects of nuclear could be much worse if India and Pakistan use about 50 weapons each. They could each make this many weapons and more. Recent studies using modern climate models suggest that the use of 50 weapons each by the two countries could throw up enough smoke from burning cities to trigger a change in climate, including a catastrophic drop in agricultural production and widespread famine that might last a decade. The casualties would be beyond imagination.

With each passing day, and every change in government that chooses to continue existing policies, nuclear weapons become more deeply institutionalized in India and Pakistan. South Asia is witnessing the triumph of “exterminism,” the system famously described by the English historian and peace activist E.P. Thompson as comprising “the [nuclear] weapons-system, and the entire economic, scientific, political and ideological support-system to that weapons-system – the social system which researches it, ‘chooses’ it, produces it, polices it, justifies it, and maintains it in being.”

The history of the past 60 years teaches that the pursuit of nuclear capabilities overwhelms both reason and morality. The past ten years of nuclear South Asia suggests the future will be grim.

Zia Mian, a Foreign Policy In Focus ( columnist, directs the Project on Peace and Security in South Asia at the Program on Science and Global Security, at Princeton University's Woodrow Wilson School for Public and International Affairs.

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