The United States, no more but no less than other states, tends to make self-centered assessments of other countries’ policies. This is one reason it missed the Iran factor as the most likely explanation for Saddam Hussein’s deliberate ambiguity about a “weapons of mass destruction” capability. Washington may be committing a similar error with respect to Iran’s nuclear motives. In projecting the threat from a potential nuclear Iran to Israel, the West keeps open the last resort possibility of a pre-emptive Israeli attack on Iran. Tehran’s security concerns and its quest for nuclear weapons may be aimed as much at meeting the Sunni threat as the Israeli threat.

Like most countries, Iran’s security policy is driven by multiple motives. Since Iraq was attacked and occupied after having disarmed, other states that fear a U.S. attack have a powerful incentive to acquire nuclear weapons to deter it. The history of Western intervention in Iranian affairs, coupled with the continuing bellicose rhetoric directed at the Iranian regime and large numbers of U.S. military forces in Iraq and Afghanistan, mean that Tehran cannot discount an armed attack. Moreover, with so many of its neighbors being nuclear armed – Israel, Russia, Pakistan, China and India – a prudent Iranian national security planner is likely to recommend acceleration, not abandonment, of the nuclear program.

Iran’s aggressive posture in the Middle East is, in part, a reaction to its fears of being overwhelmed by Sunni countries surrounding the Shia island. True, Iraq is a Shia majority, but the years of Sunni rule under Mr. Hussein and the ambiguity of Americans in finalizing the Iraqi government around its Shia majority heightened Iranian suspicions. The decade-long war against Iran by Mr. Hussein’s Sunni regime was supported by Kuwait and Saudi Arabia and politely ignored by the West and the United Nations. Iran has not forgotten that.

Tehran is opposed to Taliban domination of Afghanistan, at the expense of the sizable Shia Hazara population.

Pakistan, the world’s only Muslim nuclear power and an immediate neighbor, has the fastest growing nuclear arsenal today. In dismissing India’s warnings of a Chinese-assisted weapons program by Pakistan, Washington set the stage for India’s – and Pakistan’s – overt nuclear breakout in 1998. In neglecting the Pakistan factor as a driver of Iran’s nuclear policy, the U.S. may be reducing its leverage over Iran’s actions.

Pakistan’s growing nuclear arsenal poses two kinds of danger to Iran. The first is the possibility of Pakistani nuclear weapons falling into the hands of the Taliban or al-Qaeda, both of whom are anathema to the Iranians as much as they are to India and the West. Iran harbors suspicions that Pakistan could be the provider of last resort of nuclear material and weapons to Sunni countries hostile to Shia Iran. After all, Libya tried to buy nuclear weapons from the infamous A.Q. Khan syndicate, backstopped by Pakistan’s armed forces, and the same group was accused of helping the Iraqi search for WMDs.

If Iran’s pursuit of nuclear weapons is seen as a search for security in a hostile Sunni region, and not just as the desire to destroy Israel, it opens up possibilities of solutions other than the one based solely on the current approach. Countries in the Persian Gulf fear they form the first line of attack of a Iranian nuclear weapon. But they’re not quite ready to publicly oppose Iran’s nuclear ambitions as long as Israel has nuclear weapons. Innate caution and the ambivalence of the Gulf countries loaded with emotional hostility toward Israel make it expedient for them to leave the issue to Washington. But they should be brought into the dialogue process with Iran, just as Japan and South Korea are integral partners in the six-party talks with North Korea.

If Iran is to be dissuaded from the nuclear weapons path, a realistic assessment of its threat perception is essential. It needs reassurance against Sunni hostility as much as against Israeli and Western threats of invasion and regime change. A continued failure to grasp the security calculus behind Tehran’s interest in nuclear weapons will fail to check proliferation.

Prakash Shah is a former Indian ambassador to the UN and a UN special envoy to Iraq. Ramesh Thakur is a professor of political science at the University of Waterloo and a former UN assistant secretary-general.