The almost continuous daily artillery and rocket shelling across the border with Lebanon has killed dozens of soldiers and civilians on both sides, uprooted more than 80,000 Israeli civilians within the combat zone from their homes, and a drone attack on Hezbollah’s stronghold in southern Beirut on Tuesday has pushed the conflict's temperature to a boiling point.

Leaders in both the Israeli government and the Hezbollah militia are fully aware that the devastating war involving a possible Israeli ground invasion and Hezbollah's use of heavy long-range rockets on Israeli cities would have profoundly significant and destructive effects on both sides.

However, there was no sense that escalation could be greater than it was this week, following the killing of Hamas deputy leader Saleh al-Arouri in a drone strike bearing all the hallmarks of an Israeli assassination operation.

Hezbollah leader and prominent cleric Hassan Nasrallah appeared on video twice during the four days following al-Arouri’s death, on Wednesday and again on Friday, to warn that the alleged Israeli attack on Lebanon would not go unanswered and pledged revenge at a time and place chosen by his group.

Nasrallah said in his Friday speech, "The response is coming without a doubt," adding: "We will not remain silent over a breach of this level because this means that all of Lebanon will be exposed."

Consequences of escalation

Lebanese political analyst and Hezbollah researcher Amal Saad told CBC News that she believes Nasrallah will continue to carry out the threat.

She added, "The response will be very soon," "The deterrent value will be completely undermined if Hezbollah does not respond soon, because Israel has declared its intention to continue targeting Hamas and Islamic Jihad officials in Lebanon."

Saad, a lecturer at the Cardiff University School of Law and Politics in the UK, continued that Hezbollah, the strongest military player in Lebanon, is a political and military entity affiliated with Iran and an arch-enemy of both Israel and the United States.

Hezbollah, which boasts the best-funded and best-armed militia in the region, has the means to fulfill Nasrallah's threats; the group possesses a powerful military arsenal far exceeding what Israel faced in its war against Hamas in Gaza.

Some reports suggest that the militia can deploy more than 100,000 fighters and is equipped with over 100,000 rockets and shells, some capable of delivering massive warheads weighing 1,000 pounds (450 kg).

This is likely sufficient to destroy Israeli cities and cause significant chaos and devastation across the country.

Saad explained that she believes any retaliatory response ordered by Nasrallah will be calibrated to convey a political message but not necessarily to force Israel to respond with a harsher counterattack.

She added, "I think the response will be an escalation, but below the threshold of a high-intensity war, i.e., a full-scale and widespread war, which would provoke the kind of response that might force Israel to bomb the Beirut area."

The killing of al-Arouri represents the first time a senior Hamas official has been targeted outside Palestinian territories, and although the attack may not have explicitly targeted Hezbollah, it took place amidst one of its strongholds in Beirut.

Nasrallah routinely refers to Hamas as part of the "Resistance Axis," an informal alliance of groups and states opposed to Israel and other Western powers in the Middle East.

Analysts believe Iran is the leader of the group, providing much of the weapons and funding, not only to Hezbollah but also to the Houthi militias in Yemen, whose fighters launch rockets and attack ships near the Red Sea as part of an attempt to disrupt the Israeli economy and affect global trade.

Hezbollah and Israel fought a fierce monthlong war in 2006 that resulted in the deaths of more than 1,200 Lebanese civilians and 158 Israelis, ending with a settlement mediated by the United Nations and peacekeeping forces along the Israeli-Lebanese border.

A less severe firefight erupted again after the wide-scale attacks launched by Hamas on southern Israel on October 7, which included artillery shelling and artillery strikes across the border from both sides.

But so far, there has been no indication that the Israeli government or Hezbollah leadership wants to engage in direct ground combat.

In October, Israeli officials took a precautionary step by evacuating about 80,000 people from cities and communities within Hezbollah artillery range, but Prime Minister Benjamin Netanyahu’s government is under pressure to allow them back to their homes.

Israel has demanded Hezbollah forces withdraw to north of the Litani River, about 20 kilometers from the border fence.

In December, Defense Minister Yoav Gallant said Hezbollah must comply or Israel "will use all available means" to expel Hezbollah forces.

Gallant returned to the border area on Friday and, after meeting with military leaders, issued another statement saying, "We prefer the path of political settlement but we are close to the point where the hourglass will turn."

This week, even before the drone strike on al-Arouri, the United States sent its special envoy, Amos Hochstein, to try to de-escalate tensions and work with the Lebanese government to find a solution to the border confrontation.

Avoiding escalation

Despite Nasrallah’s fiery speech and Israeli threats, both sides have compelling reasons to avoid further escalation.

Lebanon is facing a severe economic crisis, and there seems to be little interest in fighting a war with Israel, meaning Hezbollah might risk a large violent popular backlash.

Although Hezbollah's forces are huge, some analysts believe they could still expect to suffer significant losses in any ground war involving Israeli forces equipped with modern Western-made weapons.

It is also unlikely that Iran would want to waste Hezbollah, one of its most valuable military assets, in a futile battle.

For Israel, the risks of a wider war are no less serious, says Saad, the Lebanese analyst.

As the war against Hamas in Gaza turns into a chaotic and protracted battle, Israeli military resources will be drained.

Saad told CBC News, "I think it is impossible for Israel to fight on two fronts. No army in the world, especially of Israel’s size, can do that."

This dynamic has reinforced the unstable confrontation that has lasted over the past three months, but with this week’s drone raid, it may now be on the verge of unraveling.