In the winter of 2002-2003, supporters of regime change in Iraq were upbeat in their vision of the post-invasion phase of the war. Anyone who suggested that what is happening today was a likely scenario was criticized as being a pro-Saddam appeaser, anti-American, or both.
Yet a sober assessment of the difficulties ahead would have helped to avoid many of the mistakes that have proved to be so costly in terms of American lives and resources -- not to mention the suffering of Iraqis.
Now some voices in the US and elsewhere are proposing military action against Iran.
So it is logical to ask: What are the realistic scenarios concerning the consequences of such intervention? Are there any plans regarding how to handle the post-strike situation?
Without doubt, those willing to strike -- either alone or in a coalition -- have a range of options, ranging from naval and air blockades to targeted raids, sabotage inside the country and massive attack from without. But the Iranians also have cards up their sleeve -- some predictable, some wild.
They may become malicious and aggressive in Iraq and Afghanistan. The Iranian and Syrian-backed Hezbollah militia may reinitiate hostilities. Terrorist groups, both old and newly created, may receive fresh funding and volunteers. A direct military showdown in the Gulf and the Straits of Hormuz -- through which about 40 percent of the world's traded oil is shipped -- cannot be ruled out. As a consequence, oil prices would skyrocket.
Some analysts argue that the negative effects of such an outcome would only last for months. In their view, once Iran's military capabilities and nuclear program are destroyed, the Iranians will no longer represent a threat.
However, it seems obvious that whatever happens, the Iranians will fight an asymmetric war not only on their own territory, but also in the neighboring region for years to come. As the case of Iraq shows, "months" is a long time in the Middle East.
The fact that an Iranian reaction to a military attack might be ferocious does not mean that Iran's government should be allowed to do whatever it deems appropriate.
On the contrary, the international community must be ready to enforce the most sacrosanct rules of peaceful coexistence, and sometimes this may include resorting to the use of force.
But in an interdependent and interconnected world, the use of force cannot be the result of national political calculations. Rather, it must be the product of the widest possible consensus on a critical threat assessment.
The war against Iraq in 1991 is the leading example of military intervention following global consensus. If such a consensus cannot be reached, at least Western powers and like-minded states must agree, as in Kosovo in 1999, for example. The third possibility -- military action endorsed by a small group of states -- should be avoided, for practical, legal and moral reasons. Today, efficiency of external action is inextricably linked to its legitimacy.
When it comes to deciding on how to deal with Iran, the US and its allies should bear in mind the following principles.
First, it is crucial to make a rational threat assessment. Learning the lessons of the decision to invade Iraq, democracies should not allow personal obsession, fantasy and dogma to contaminate the foreign policymaking process. It is essential to distinguish between what we know, what we ought to know -- and what, therefore, we would like the Iranians to tell us -- and what is speculation. Alarm bells signaling that the time to take action has arrived should ring at the right moment, and not before.