Among many bald statements, one stuck out: Israel is now ready to destroy three or four nuclear sites out of 12 in Iran. "I believe that Israel is planning to act on these reactors before Bush leaves the White House," Mr Aviv said. "We've got to take a chance … the next president of America may not allow it."

Mr Aviv admits that the downside would be a huge backlash across the Middle East, and a search for ways to strike back at Israel and, failing that, at Jewish targets worldwide (which would mean more call for the services of people like him). But, he says, the immediate danger to Israel from Iranian nuclear weapons will be set back for 10 or 15 years. He may or may not be speaking for anyone but himself, but his sponsorship suggests Australian opinion-makers were being warmed up for an Iran strike. If so, it's an unsatisfactory level of discussion, and surely cannot reflect policy debate in a nation as sophisticated as Israel.

But, as pointed out in Sydney by another senior Israeli figure, David Kretzmer, an emeritus professor of law from the Hebrew University of Jerusalem, overseas Jewish communities are often more passionate and less nuanced in their defence of Israeli interests than people living in Israel. We'd perhaps better hurry, but it would be nice to have some discussion about the alternatives to the immediate strike option, and that option's drawbacks.

One would be to see if a change of US president, and a farewell to George Bush and "Axis of Evil" talk about Iran, can bring new life to the international diplomatic effort to halt Iran's shift into highly enriched uranium capability. Another option would be to live with the Iranian nuclear threat. After all, we in the West did that for 40 years with the Soviet nuclear deterrent. Israel might have to declare its own nuclear arsenal, thought to include about 200 warheads, and take extra precautions to ensure its survivability - although it is said to have several warheads fitted to cruise missiles on submarines.

Deterrence assumes normal rationality and interest in self-survival in the opposing country of the "balance". Many Israelis will be quick to point out this can't be assumed in a "fanatical" regime like that of Iran's Mahmoud Ahmadinejad, and that Jews draw an extraordinary level of hatred. Still, mutually assured destruction has proven a pretty powerful persuader to keep missiles secure in their silos and crazy fingers off launch buttons.

In addition, the Iranians would have to factor in the interests of the people they are supposed to be helping. Some Palestinians have already pointed out that most of their population would also fall victim to any nuclear bombs that reached Israel. The Syrians and Hezbollah members in Southern Lebanon might also like to think about this. Another downside of the strike option is that neither the US nor Israel can be sure that they know and can take out all the key nuclear weapons facilities in Iran's dispersed and deeply buried network. Or that other types of weapons of mass destruction are not being developed in parallel. Israel developed its bomb not because it thought it an essential part of being an independent state, but as a precaution against any of its regional enemies getting one.

As the Israeli politician Yossi Beilin once explained to a group of reporters in New Delhi, this set it apart from the Indians or Chinese. Unlike India, Israel would be ready to trade its bombs away in a genuine and all-inclusive regional non-nuclear pact. Even if the strike does buy 10 or 15 years' space from Iran, it is only likely to deepen the hatred surrounding attempts to negotiate a peaceful settlement of Israel's position in the Middle East. It looks like hard thinking, but it's putting off the really harder thinking.