For more than 40 years, a bloody and violent shadow war has been raging between the Israeli secret services and the militant Shiite Islamist organization Hezbollah based in Lebanon.

One of Israel’s earliest defeats came in November 1982, five months after its forces invaded Lebanon to destroy the Palestine Liberation Organization based there. When the PLO’s armed fighters were forced to leave Beirut, it seemed as if Israel had won a major victory.

Then there was a massive explosion that destroyed the headquarters of the Shin Bet, Israel’s secret service, in the coastal city of Tyre. The explosion killed 91 people. The authorities at the time and for years afterwards blamed a gas leak for the explosion.

In fact, it was a massive suicide car bomb attack, one of the first of its kind organized by militant Islamists from the Shiite population of southern Lebanon.

The masterminds of the attack later joined Hezbollah, which was founded the following summer under the supervision and support of the new Iranian revolutionary regime that had taken power in Tehran in 1979. The same young radical Shiites carried out another successful bombing attack on the Shin Bet headquarters in Tyre in November 1983, killing 28 Israelis and 32 Lebanese prisoners. They also claimed hundreds of victims in the United States and France in other massive suicide bombings that Israeli security forces were unable to prevent.

This marked the beginning of one of the world’s most bitter secret conflicts of recent decades.

The Israeli military fought Hezbollah until it was forced to withdraw from Lebanon in 1999 and again during a brief war in 2006. But the country’s intelligence services remained undeterred.

Due to an acute lack of intelligence, the Israelis remained in the dark about Hezbollah’s plans for much of the 1980s. The whereabouts of one particular individual – a young Lebanese Shiite named Imad Mughniyeh who had planned bombings, hijackings and kidnappings – remained unclear. There were several near misses, but it took more than 20 years for the Israelis to catch up with their loot after Mughniyeh was killed by a car bomb in Damascus in 2008.

An important battlefield in the early 1990s was South America, where Hezbollah managed to recruit support from Lebanon’s large Shiite diaspora.

When Israeli attack helicopters killed Abbas al-Musawi, the new leader of Hezbollah, in southern Lebanon in February 1992, the militant Islamist organization sought revenge in Argentina. First, the Israeli embassy in Buenos Aires was bombed, killing 29 people, and then in 1994 a suicide bomber killed 85 people in a Jewish community center in the Argentine capital. Investigators blamed Hezbollah for both attacks.

South America also proved to be a major hub for Hezbollah’s funding, with followers there conducting a variety of legal and illegal activities that brought the organization enormous sums of money. The sheer scale of the operations, often conducted from remote locations where local security services had limited presence or knowledge, complicated Israel’s efforts to stop them.

In recent decades, Europe has been another theatre of hostilities in the shadow war.

As Hezbollah sought to expand its logistics operations on the continent through dozens of companies, Israeli intelligence services tried to block the group’s efforts. A series of low-profile operations had some success, many thanks to discreet support from local security services. A Hezbollah attempt to avenge Mughniyeh’s death with an attack on the Israeli embassy in Azerbaijan was thwarted. But then in July 2012, a suicide bombing on a bus in the Bulgarian Black Sea resort of Burgas killed five young Israelis and a driver. Investigators found evidence of links to Hezbollah.

By then, the battle was already raging around the world. In 2012, US intelligence analysts discovered several Hezbollah attacks on Israeli or Jewish targets in just six months – including two in Bangkok and one each in Delhi, Tbilisi, Mombasa and Cyprus. A diplomat in Delhi was injured in a series of magnetic car bomb attacks. The action was part of a complex operation involving agents in Thailand and India, some of whom had links to Iran and Hezbollah.

North America is primarily a logistical hub for Hezbollah, with major financing operations at the forefront. These have reportedly enabled sympathizers to transfer hundreds of millions of dollars to Hezbollah, a key source of funding for its extensive social budget and military operations.

In 2011, US authorities alleged that proceeds from car sales and drug trafficking were being funneled back to Lebanon through money laundering channels controlled by Hezbollah. Last year, a prominent art collector was placed on a US Treasury sanctions list and indicted in the US on charges of using his collection, which includes masterpieces by Pablo Picasso, Antony Gormley and Andy Warhol, to launder money for Hezbollah.

And then there was the clandestine war that was taking place closer to home. In 2023, David Barnea, the director of Mossad, Israel’s main foreign intelligence agency, described 27 Iranian plots against Israelis, including in Georgia, Cyprus, Greece and Germany. Hezbollah operatives were active in Iraq, Yemen and Syria, where thousands of its fighters were deployed during the civil war.

While there have been victories and defeats on both sides over the decades, the balance seems to have shifted decisively in Israel’s favor in recent months.

Israeli officials have reported attempts by Iranian activists – or Hezbollah – to carry out attacks in Israel. None of these attempts have been even remotely successful.

Last week’s pager attacks, which killed 37 people and injured around 3,000, are attributed to the Mossad and other Israeli intelligence agencies and are seen by analysts as a resounding victory in the long, secret conflict.

At the same time, Hezbollah’s high command was weakened by a series of Israeli assassinations of senior military officials. This suggests that there was timely, accurate intelligence from within Hezbollah, likely derived from a mix of intercepted communications, surveillance, and agents within Hezbollah’s ranks.

“This is a huge intelligence coup … The Israelis are targeting the top and middle levels and that is making (Hezbollah) blind, deaf and mute,” said Magnus Ranstorp, a veteran Hezbollah observer at the Swedish Defense University.

The targeted assassinations also show that the Mossad and other intelligence services have a long institutional memory.

Fuad Shukr, the Hezbollah chief of staff killed by Israel in July, and Ibrahim Aqil, killed last week, were key members of Hezbollah’s current military hierarchy and would have played important roles in any coming full-scale war. Both were also founding members of Hezbollah and part of the network responsible for the 1982 and 1983 bombings.