Concerns over the Gaza conflict spreading to other parts of the Middle East tend to focus on the opening of a “second front” on Israel’s northern border, where Hezbollah has been peppering Israeli military positions with fire from mortars, rockets and anti-tank weapons for almost two weeks at a cost to itself of more than two dozen fighters. Israel has evacuated towns in the border region as a precaution. While the fighting there will continue to be a deadly irritant, how likely is it to open up as a second front in this war?
Hezbollah is the jewel in the crown of Iran’s regional partners and proxies. It is one of – if not the – most capable armed non-state actors in the world. In reality, it is a semi-state actor given it long ago shed its disdain for domestic Lebanese politics and is now not only a part of the Lebanese government, it is effectively its kingmaker. It has also come a long way from its formation in the early 1980s under Iranian tutelage, when it attacked Israeli forces in Lebanon and in its early days battled for primacy with its Lebanese Shiite competitor Amal.
But its role within the Lebanese political establishment also acts as a constraint in the current conflict. For a country in the midst of perhaps its worst economic crisis in history, any Israeli retaliatory attack on Lebanon that damaged infrastructure would also damage Hezbollah.
The organisation learnt that lesson in 2006 when its attack on an Israeli military patrol initiated a month-long war in which Hezbollah performed well militarily but Israel inflicted significant damage on Lebanon, particularly in the south, a Shiite heartland. Many of Hezbollah’s supporters criticised the party for inviting Israeli military retaliation over an operation of limited utility to the Lebanese Shiite community, or the broader anti-Israel cause.
While Palestinians in Gaza may see no alternative to enduring suffering to achieve their goal of a Palestinian state (however so defined), Lebanese see no need to suffer on behalf of any Palestinian cause. Indeed, the 12 Palestinian camps in Lebanon that have been there for more than half a century have not only been a blight on the international community but at best an irritant, and at worst a security threat, to the Lebanese. There is no stomach in Lebanon to bleed for the Palestinians. Lebanon is not Gaza, and Hezbollah is not Hamas.
Iran, too, will be wary of having Hezbollah overcommit or be weakened. Ties between Hezbollah and Iran are much deeper than between Iran and Hamas at all levels: ideologically, operationally and politically. Given the centuries-old links between the Shiites of Lebanon and Iran, Tehran’s role in forming the organisation and Hezbollah’s own military competence, in many ways Iran sees Hezbollah as a partner rather than a proxy, and as a strategic asset in a way that it doesn’t view Hamas.
Hezbollah will remain engaged in the fight, but not decisively so. It isn’t in Tehran’s strategic interest for Hezbollah to be degraded along with Hamas. Hamas has already offered some veiled criticism that groups such as Hezbollah aren’t doing enough to support it on other fronts. Hezbollah’s deputy leader, Naim Qassim, meanwhile, has said it is engaged in the fight and its actions have kept three Israeli divisions deployed in the north that could otherwise have been used in Gaza.
Fighting on Israel’s northern border will continue, albeit within largely accepted rules of behaviour. Hezbollah can’t portray itself as a resistance movement against Israel if it isn’t seen to be engaging in the current fight. And the fact that Israel has to retain assets in the north that it could be deploying in Gaza does mean that Hezbollah’s limited engagement is of benefit to Hamas. But Hamas should not expect Hezbollah to do anything that risks an overwhelming response from the Israelis. For all the rhetorical support for the Palestinian cause, there are limits to what Hezbollah will sacrifice in pursuit of it.
This adherence to the rules of the game is likely to continue for the foreseeable future with changes in intensity along the way. However, the problem with a relatively ill-defined set of rules defining “acceptable” military action by Hezbollah is their very lack of definition. Nobody knows exactly what the red lines are.
In the past few days, though, Israel’s Prime Minister, Benjamin Netanyahu, made those lines clear: “If Hezbollah decides to enter the war, it will long for the Second  Lebanon War … It will be making the mistake of its life. We will strike it with strength that it cannot even imagine and the significance to it and to the country of Lebanon will be devastating.”
So while it is unlikely that Hezbollah will open any second front on Israel’s northern border in support of Hamas, the attack of October 7 was unprecedented in its ferocity. Israel’s ground operation will generate enormous anti-Israeli hostility in the region. Given the febrile atmosphere that pervades the region currently, the possibility of accidentally breaching the accepted rules of the game are magnified. Hezbollah, however, does not see unfettered support for Hamas as a hill it wishes to die on.
Dr Rodger Shanahan is a former army officer, Middle East analyst and the author of Clans, Parties and Clerics: the Shi’a of Lebanon.