Ideology is in my view the cardinal sin in politics. Ideology means not bothering to think about the real problem, just apply a ready made one size fits all solution. It does not matter which side of the aisle the ideologues sit, they cause fiasco at best, at worst they blindly lead a Hitler or a Stalin.
In that respect the news that the Iranian mullahs are as corrupt and venal as they come is good news. When it became clear that the comrades of the Soviet Union were as corrupt as they come mutually assured destruction became a viable strategy.
When a politician states that an outcome is 'unthinkable' they should be considered unfit to lead. If you can't think the unthinkable you can't make a rational choice between the possible outcomes.
The worst possible outcome of the current situation in the middle east is a world war. Threatening Russia and China's oil supply is a good way to start one.
The most likely effect of starting a preventive war against Iran is that the power of Iran will grow. The bulk of the world's oil supply has to flow through the Straits of Hormuz Iran in slow moving, easily sunk oil tankers. Iran has the ability to retaliate. If Iran is attacked it will have the opportunity to demonstrate the importance of this fact.
Israel has over 200 nuclear weapons. That is more than enough to discourage nuclear blackmail. Treating the acquisition of nuclear weapons by Iran as equivalent to the immediate destruction of Israel is false and dangerous.
If Iran does acquire nuclear capability Israel might well be safer. Unilateral nuclear capability is dangerous in itself, it encourages the type of aggressive militarism that led to the disaster in Iraq. When Iran acquires a nuclear capability expatriate irridentists are going to have to face the fact that the choices they demand are not costless.