Unlike in 1981, when Israel destroyed Iraq’s nuclear reactor at Osirak, there is no single target. A sustained bombing campaign would end up killing many civilians and still might not cripple Iran’s nuclear program. Tehran also has many frightening ways to retaliate. And even Arab states who fear Iran shudder at the thought of America, or its ally Israel, bombing another Muslim country and the backlash that that could provoke.

Mr. Olmert may be trying to divert attention from his political troubles. Still, there is no denying a growing and understandable sense of urgency in Israel, which Iran’s president has threatened with elimination. A recent report by United Nations inspectors on Iran’s nuclear progress, and worrisome links to military programs, has only fanned those fears.

Javier Solana, the European Union’s foreign policy chief, is scheduled to visit Tehran later this month to discuss, in more detail, an incentives package first offered in 2006 by the United States and other major powers. It is likely to fall far short  both in incentives and punishments  of what is needed to get Tehran’s attention.

There is no indication it will contain tougher sanctions  including a broader ban on doing business with Iranian banks and bans on arms sales and new investments. It also needs a stronger commitment from Washington to lift sanctions and to fully engage Iran if it abandons its nuclear efforts. The United States is the only major power not sending a diplomat with Mr. Solana.

Senators Barack Obama and John McCain disagree on holding direct talks with Iran (Mr. Obama would; Mr. McCain would not). But last week, both endorsed enhanced sanctions, including limiting gasoline exports to Iran. That is an idea well worth exploring. Iran relies on a half-dozen companies for 40 percent of its gasoline imports. The United Nations Security Council is unlikely to authorize a squeeze, but quiet American and European appeals might persuade some companies to slow deliveries, and it would grab Tehran’s attention.