Israel–Hamas war forecasting: Israel's simmering conflict with Hezbollah could easily intensify

Israel–Hamas war forecasting: Israel's simmering conflict with Hezbollah could easily intensify
Illustration by Laurel Molly, © All Rights Reserved
  • Median scenario has Israel–Hezbollah fatalities between 500–1,000 in 5 months' time
  • The US has conducted lethal airstrikes on Iranian forces
  • 3.3% chance of a major escalation (100+ US–Iran deaths) in the next 5 months
  • Updates to all of our previous forecasts on the Israel–Hamas war

Last month, we published a report 6 days after the 7 October attack, where our forecasters claimed that there was just a 20% chance that Hamas would be governing Gaza City on 13 April 2024. Now, a month later, it appears that Hamas has already lost de facto control of the city, with pictures circulating on social media of the Israel Defence Forces' Golani Brigade inside the city's legislative council building. The current main strongholds of Hamas in Gaza City are located in or under the al-Quds and al-Shifa hospitals. Al-Quds ceased to function on Sunday, 12 November, and (on the day of publishing this report) the IDF are reported to be inside al-Shifa hospital and conducting a "targeted operation against Hamas".

The aggregate of our forecasters' latest probabilities on Hamas' chances of having control of Gaza City in five months' time comes to under 2%, indicating that there is only a remote chance that Hamas will regain control in that time.

One forecaster, assigning 7% to this outcome, says "Israeli strategy seems to be now to focus on the north and really destroy Hamas infrastructure there," making reference to the Gaza siege plan shared by Naftali Bennett, the former prime minister of Israel. Additionally, Benjamin Netanyahu's statements that this is Israel's "second War of Independence" and will be “long and hard" suggests the IDF may stay in Gaza for a while, as do his statements saying that he thinks "Israel will for an indefinite period have security responsibility".

Most forecasters can only envision Hamas with de facto control of Gaza city in five months if the IDF, for whatever reason, prematurely withdrew from the city.

It is now very likely that this war will be deadlier than all previous Arab-Israeli conflicts

In last month's report, forecasters also said that it was likely (at 61%) that deaths in Gaza will exceed 25,000 before 13 April 2024 — a death toll higher than any previous Arab-Israeli conflict. Since then, the group's forecast has risen to 91%.

The forecasters' death toll projections increased as a result of the death toll rising to over 10,000 before the start of the ground invasion, and because they do not expect international calls for a ceasefire to be heeded any time soon.

While the death toll figures are disputed, and are naturally very uncertain, the sense among the group is that the numbers produced by the (Hamas-led) Gaza Health Ministry can reasonably be relied upon, having looked through the historical reliability of their figures. Several forecasters believe the figures being reported since the start of the ground invasion will be significant underestimates of the true figures, as the chaotic situation makes it unlikely that the deaths of militants in tunnels will be recorded.

While the IDF has now entered a different stage of the war, observations of how the war has been conducted thus far provides insights into Israel's and Hamas' mindsets. It is evident from statements by leaders of both the IDF and Hamas that minimising the loss of civilian lives has been, at most, ancillary to their military objectives.

The 31 October airstrikes that killed hundreds of civilians living in the Jabalia refugee camp — an urban agglomeration with more than 100,000 inhabitants — were conducted to take out Ibrahim Biari, a suspected leader of the 7 October attack, according to the IDF. In an interview with Wolf Blitzer on CNN, an IDF spokesperson confirmed they knew these strikes would kill many innocent civilians, replying that "this is the tragedy of war, Wolf".

Prior to that, Hamas chief Rasha Nabil said the following in response to a question about civilian deaths:

Nations ... are not easily liberated.

The Russians sacrificed 30 million people in World War II, in order to liberate it from Hitler's attack. The Vietnamese sacrificed 3.5 million people until they defeated the Americans. Afghanistan sacrificed millions of martyrs to defeat the USSR and then the US. The Algerian people sacrificed 6 million martyrs over 130 years.

The Palestinian people are just like any other nation. No nation is liberated without sacrifices.

What forecasters have been paying most attention to

Swift Centre forecasters have continued following events closely, and have paid particular attention to the potential for the conflict to widen and involve Hezbollah and Iran to a greater extent. With Hezbollah in particular, there have been several escalatory developments since the ground invasion started, such as the injuries to Israeli civilians from anti-tank missiles fired from Lebanon, reports that Hezbollah is acquiring Russian air defence systems from Syria, and their first use of explosive drones.

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Currently international attention and outrage is focused on the plight of civilians in Gaza. However, the opening a major front in the north by direct attacks from Hezbollah against civilians would change the narrative and lower pressure on Israel to seek an immediate ceasefire in Gaza. It would additionally complicate operations for the IDF as they would need to fight on two fronts, and the US may be drawn directly into the war, likely with airpower.

Full-scale war between Hezbollah and Israel is possible, but unlikely before April

Hezbollah is estimated to have approximately five times the military capacity of Hamas, with upwards of 150,000 rockets and missiles. Their arsenal is much more sophisticated than Hamas', with some missiles having the ability to reach southern Israel and having much larger payloads and higher precision. Since 8 October there have been a series of low scale border skirmishes between Israel and Hezbollah that have not escalated into a broader war, though these clashes have resulted in many fatalities: 74 Hezbollah members and 10 Israelis have reportedly been killed.

In our 13 October report, forecasters gave a 56% chance of there being 500+ Israel–Hezbollah fatalities over the subsequent 6 months due to the multiple fatal skirmishes between Hezbollah fighters and Israelis that were witnessed early, and because they expected Hezbollah to escalate their activity in response to Israel's ground invasion.

In their most recent forecasts, the forecasters believe there is a 69% chance of 500+ Israel–Hezbollah fatalities over the course of 7 October 2023 – 13 April 2024.

Hassan Nasrallah, the leader of Hezbollah since 1992, gave his first speech since the 7 October massacre on 3 November, and a follow-up speech on 11 November. He called for resistance against Israel, emphasizing the support Hezbollah has provided Hamas by engaging Israel on its northern border, preventing the IDF from devoting all its resources to the assault on Gaza. Despite the heated rhetoric and earlier threats of escalation if Israel conducts a ground war on Gaza, no significant increase in hostilities with Hezbollah have materialized, and Nasrallah has called for no larger war. For now, both Iran and Hezbollah appear to be avoiding a full confrontation with Israel and the United States.

Yet most forecasters do not envisage the conflict at Israel's Northern border cooling down any time soon. One says:

Strikes are now deeper inside enemy territory, so gradual escalation is likely. Fighting could die down but, for as long as fighting in Gaza continues, Hezbollah can hardly stop doing anything or they'll look weak. Plus there is always a chance for a big escalation that sees 500 deaths in a week or so.

This continuing low-level conflict, and the strategic importance for Hezbollah of appearing strong alongside Hamas, explains why forecasters still put a high 69% probability on Israel-Hezbollah fatalities exceeding 500 over the next 6 months, despite Nasrallah's calls to avoid further escalation.

35% chance of 1,000+ Israel–Hezbollah fatalities in 5 months' time

We asked our expert forecasters a nearly identical question, but with the fatality threshold set to 1,000, as an indicator of a more intense escalation. The aggregate forecast was 35%, with individual forecasts ranging from 10% to 50%. While not probable, this suggest that there is a considerable risk of the simmering Israel-Hezbollah conflict becoming much more intense within the next 5 months.

One forecaster commented:

Nasrallah's speech came after two massive bombings, one day after the other, in Jabalya that devastated entire neighbourhoods, including civilians. If this was not enough to bring Hezbollah more fully into the war, I doubt much will cause an escalation. I'm not lower than 32% because of the inherent unpredictability of war.

Another said that they "still believe Hezbollah does not want all-out war or by now they would have started it". Still, this forecaster views the likelihood of reaching the 1,000 death threshold as a coin flip because, as they go on to explain, "Israel might consider the job in Gaza done in a few months and decide to go after Hezbollah". This forecaster suggested this possibility in our 13 October report and, since then, leaked information suggests that the idea to move in on Hezbollah quickly has already been seriously considered by the IDF (but the US said 'no'). Additionally, while it is not possible for us to verify such claims, it is suggested that most of the IDF is not in Gaza, but instead deployed near the border with Lebanon.

Considering all of this, and commenting on the role of outside influences, a skeptical forecaster provided the following reasoning:

To understand Israel's incentives it's important to study and learn the lessons of history. When do small countries, backed by larger countries, start wars that they otherwise wouldn't have? The answer is when the larger country gives the smaller one a blank check to do so … the US has made clear it is not giving Israel a blank check to move in on Hezbollah and instead is deploying its military assets to deter Hezbollah itself.

Escalation with Iran

In our second report, published on 16 October, we focused on the degree to which Iran becomes more directly involved in the conflict while analysing the chances of the conflict escalating internationally.

In that report, we considered whether Israel would launch a missile or aerial attack on Iran within the six months subsequent to the report, defining a 'major attack' as one involving three or more missile or aerial strikes on either military sites (killing at least 5 military personell), economic targets (such as oil production, refineries, or ports), key nuclear sites, or other significant targets such as major government buildings. (Attacks that merely target and eliminate a few operatives on the ground would not be considered 'major').

There is still a possibility that Israel will launch a major attack against Iran

Last month we assigned 21% to this possibility, but the aggregate forecast has since dropped to 14%.

The core reason for the group perceiving this as less likely is a result of Israel being careful not to pin the blame of the 7 October attacks on Iran, as well as Iran distancing itself from the attacks via proxies such as Hassan Nasrallah. Nasrallah's non-escalatory speech represents Hezbollah, but it can also be interpreted as an indication of Iranian thinking. While expressing support for Palestinians, it was not a call to total mobilization. "This is indicative of a desire to deconflict yet still appear relevant," says one forecaster.

The US has already attacked Iranian forces, but significant escalation remains very unlikely

We put a 9% chance of there being a fatal confrontation between the US and Iran in a six-month period in our previous report. Since then, the US has launched multiple (26 Oct, 8 Nov, 12 Nov) precision airstrikes on the Islamic Revolutionary Guard Corps (IRGC) in Syria, the latest of which reportedly killed eight Iranian fighters. As the IRGC is a branch of the Iranian Armed Forces, the criteria of that question appear to have been met.

As a successor question, we asked our forecasters whether the total number of fatalities in US–Iran confrontations would reach 100, to signify the chances of a major escalation within the next 5 months.

The group's view is that there is only a remote chance of this, but the potential for escalation certainly exists. Here is one of our forecasters outlining their thinking:

The January 2020 Iranian ballistic missile attack on US airbases in Iraq caused at least 110 injuries (source) so it's not hard to imagine a missile attack that kills that many, given the right target.

As far as a repeat of the Iraq War but in Iran this time, it seems unlikely that the US has any appetite for this. Iran has a population of 88 million, compared with Iraq in 2003 with only 27 million. Iran is also almost 4x bigger in land area, with much more difficult terrain for an invader.

For its part, Iran also has disincentives to go to war with the US, due to the US's vast superiority in airpower, technology and intelligence, which brings the ability to greatly degrade the country's regime even in the absence of a land invasion.

In recent decades Iran has favored using proxies rather than direct confrontation. In looking at economic data, Iran has struggled to get its per capita real GDP even back up to 2011 levels (source), and any sort of military conflict with the US would be economically disastrous.

Overall then, the odds ... are pretty low, but given all the drone and other attacks on US forces in Iraq and Syria over the past two weeks, these odds are definitely not zero.

A decent portion of our forecasters emphasised the degree to which the Biden administration will try to avoid such an outcome. One says they "think that Biden's admin are very keen for this to NOT happen, which is why they are deploying so much force to the eastern Mediterranean" and another observes that "the Biden Administration seems eager to avoid a full-blown conflict with Iran, which is what this would probably represent". "The last thing they want to do is put themselves in a position where Biden will need to be making calls to families to let them know their son/daughter died," said another forecaster.

Rounding up

The final question that we covered last month was on whether a European city will see rioting on the same scale as the 2011 London riots. Our aggregate forecast remains essentially the same, down from 18% to 17%. If you would like to get an understanding of how forecasters have updated their thinking after witnessing the multiple large-scale protests since our previous report, we recommend interacting with the forecast graphic below:

Overview graphic

Illustration by Laurel Molly ©