Israel is one of three countries that launched a pre-emptive strike against the nuclear facilities of an adversary. The other two, by the way, are Iran and Iraq. They both tried to neutralize each other's nuclear facilities at some point of the Iran-Iraq war, without success, by the way. Israel has done that not once but twice, with Iraq in 1981 and with Syria in 2007. So if one judges Israel's pronouncements and posture by its history and precedent, one would assume that the Israelis are prepared, even if not ready or willing, to do it again. I think that the Israelis believe they have the capability to launch a strike that would achieve a measure of success they can live with, maybe not as disruptive as an attack by the combined forces of allied countries in the west led by the United States, but certainly one that could gain Israel a number of years.
I don't think the Israelis are at the stage of making that decision yet. I think that with all the talk of war we have heard in recent weeks and months, the fact that the Israelis have waited until now tells us how reluctant they are to go forward with this kind of operation. In both the Iraqi and the Syrian case, Israel acted at the very early stages of progress of those two nuclear programs. We are way past that moment today.
To the question of how far the Iranian program has gone and whether the Israelis have cause, again I have to defer for a complete answer to classified information I do not have access to, but based on the open sources that I have access to and that I have read, my judgment is that the question hinges more upon the kind of political thinking that is happening within the senior ruling elites in Tehran and has less to do with technical issues. Iran has proven capable of enriching uranium to nearly 20%. It has the technical ability to go all the way to 90% if it so wishes. It may take a few months, but capability-wise, Iran is there already. There is enough evidence in IAEA reports that Iran has conducted extensive experiments with the components of a nuclear device, and it may be significantly closer to being able to miniaturize a warhead to install it on a ballistic missile.
Iran may be also conducting activities related to a military program in a covert fashion. The fact that we do not know of any covert facility does not mean that there isn't one, for the very simple reason that Iran's nuclear program's history is one where much of the activities related to the military dimensions of the program and the enrichment were being conducted in a covert fashion. The fact that these facilities were exposed was actually a significant setback in the timeline of the program, but it's a fact that Iran has always done things covertly.
What would happen if an attack occurred? What would Iran do? There are two schools of thought here. One says that Iran is a rational actor. If Iran is rational and calculates, my instinct would be to say that a limited attack on its nuclear facilities would not unleash all of the reprisal tools that Iran has at its disposal. Iran would probably focus on responding to Israel first by unleashing Iranian proxies in the Levant by having Hezbollah and Hamas launch missile attacks on Israel and initiate hostilities on Iran's behalf, and secondly by launching and trying to execute a number of terrorist attacks on soft targets overseas against both Israeli diplomats and diplomatic missions, as well as Jewish centres across the world.
I doubt that a rational Iran would engage in the kinds of activities that would draw the United States to come to Israel's side.
The second school of thought, of course, says the opposite, which is that Iran is not a rational actor, and if attacked, it would unleash every single tool it has in its arsenal. In addition to the things I've described, it could conceivably target critical civilian infrastructure on the Arabian shore of the gulf. It could seek to target western troops—NATO troops stationed in Afghanistan, U.S. troops in the gulf. It could try to close the Strait of Hormuz, of course.
It could try to do a number of additional extreme and disruptive actions that would have a tremendous impact, at least in the short term, on the global economy.
The decision to attack is therefore one fraught with danger and risks, and I think that is the reason, mainly, why Israel so far has held itself and is still giving time to the possibility that sanctions and negotiations will yield a result.