WATERLOO, Ontario — The United States, no more but no less than other countries, tends to make self-centered assessments of other countries' policies. This is one reason Washington 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. Iranian security concerns are focused as much to the east on Pakistan as to the west on Israel. Iran's quest for nuclear weapons may be aimed at meeting the Sunni threat — not just the Israeli threat.

Of course, like most other countries, Iran's security policy is driven by multiple motives. Also like others, while it may hope for the best, Iran must be prepared for the worst. Since Iraq was attacked and occupied after having disarmed, other countries who have reasonable cause to fear a U.S. attack have a powerful incentive to acquire nuclear weapons to deter such an attack.