MELBOURNE, Australia — Is Iran hellbent on becoming a nuclear-armed state? Or will it settle for nuclear capability, able to make weapons but choosing not to? Does that matter?

Few international questions involve higher stakes than these. An immediate concern, if deep pessimism about Iran's intentions prevails, is whether the Israelis will mount a preventive strike, leading to another major Middle East war — with catastrophic consequences for the global economy likely.

No one should underestimate the difficulty of assessing Iran's real intentions. Mixed signals from competing power centers don't help; nor does the recurring contrast between Iranian officials' usually strident public pronouncements and often-moderate private discourse.