While Hezbollah can still draw lessons from Israel's current ground incursion into Gaza, as well as from previous operations such as Pillar of Defense and Cast Lead, it recognizes that a conflict with Israel in Lebanon would be quite different because of variables including the geography and the battle space.
Israel and Hezbollah learned several lessons from the 2006 Lebanon war. For the Israeli military, it was clear that airpower alone could not halt or even significantly curtail Hezbollah's rocket fire into Israel. In fact, Hezbollah was able to launch hundreds of rockets into Israeli territory up until the last day of the conflict, and Israel's operations in Gaza since then have only reinforced the necessity of ground troops. In the meantime, Hezbollah's rocket inventory has increased both in quantity and quality, representing approximately 10 times the arsenal that Israel Defense Forces are contending with in Operation Protective Edge. Compared to militants operating in Gaza, Hezbollah has a much better supply line to replenish its resources with its relative freedom of operation.
It is important to remember that Israel's Iron Dome defense system, while seemingly effective against rocket attacks by Gaza militants, would be unlikely to fare as well against Hezbollah. Hezbollah has the space, equipment and personnel to launch simultaneous mass salvos of rockets at Israel, overwhelming the limited number of Iron Dome batteries. Gaza militants on the other hand — with their smaller rocket inventory and lack of strategic depth, as well as Israel's pervasive intelligence, surveillance and reconnaissance network — have largely been unable to fire off mass salvos.
Until the advent of systems that use lasers to prematurely detonate enemy rockets in flight, the cost disparity between the offensive rocket and the interceptor missile is also heavily weighted in the attacker's favor. Also, Israel's countermeasure for Hezbollah's longer-range rockets and ballistic missiles, the David's Sling system, is not operational and remains an unproven weapon.
The Winograd Commission, which Israel set up to draw insights from the 2006 Lebanon war, lambasted the quick decision to go to war and heavily criticized the hesitant pursuit of the conflict once Israel Defense Forces were engaged. To counter Hezbollah's vast rocket arsenal and maintain the initiative, the Israeli military would likely mount a powerful ground offensive into southern Lebanon in a future serious conflict with Hezbollah.
A new Israeli offensive into Lebanon would aim to disrupt and degrade Hezbollah forces while clearing the rocket-launching areas closest to Israel. Hezbollah maintains a significant number of long-range rockets and missiles that can strike Israel from as far away as the Bekaa valley, but the vast majority of its arsenal consists of shorter-range, Grad-type rockets whose reach and effectiveness would suffer significantly from an Israeli push north. The large number of underground bunkers and imperfect Israeli intelligence would theoretically allow Hezbollah to continue firing rockets from behind the Israeli advance, but the dearth of heavily built-up areas south of the Litani River and the considerable presence of Israeli ground troops would mitigate the success of such tactics.
Instead, Hezbollah would more likely prioritize its attacks on Israeli army columns while continuing to fire rockets from secure territory, thus avoiding needlessly risking its limited inventory of bulky and visible multiple rocket launchers.
On a more tactical level, Israel Defense Forces have focused heavily on developing a counter to Hezbollah's effective use of anti-tank guided missile systems during the 2006 conflict. They have fielded the Trophy active defense system on the heavily armored Merkava Mark IV main battle tank, for example, and the system has already proved successful in a number of incidents along the Gaza border.
For its part, Hezbollah relies on its use of bunkers and concealment, a tactic that proved effective in the last war. Hezbollah has also modified its placement strategy for improvised explosive devices to account for Israel's successful use of D-9 armored bulldozers to clear improvised paths and successfully avoid mined roads. Hezbollah also remains concerned about the high attrition rate of its experienced fighters in the Syrian civil war, and it has already started to shift less experienced new recruits to Syria while holding back its veterans.
Hezbollah continues to grow its rocket arsenal while Israel expands its missile defenses, but while rocket attacks and missile intercepts would undoubtedly figure prominently in any future Hezbollah-Israel conflict, both sides know the conflict would ultimately be decided on the ground.
