For years, Israel has relied on the invisible shield of its sophisticated Iron Dome air defence system to protect its citizens.
Since it became operational in 2011, it has intercepted thousands of missiles, rockets and drones from Hamas and Hezbollah, according to the Israeli military.
But now experts say the mighty dome is being put to the test like never before.
Israel and Hezbollah are locked in their most intense round of fighting in decades, teetering on the brink of all-out war.
Israel has been unleashing air strikes across Lebanon, killing more than 600 people and injuring thousands more, according to official government updates from Beirut.
The prime minister's office said the strikes would continue until the 60,000 citizens evacuated from northern Israel due to Hezbollah's bombings could return home.
But at any moment, Hezbollah could retaliate with powerful missiles and swarms of rockets capable of overwhelming Israel's air defence systems.
The Lebanon-based militant group is widely deemed the most powerful member of the Iran-backed network, known as the Axis of Resistance.
Experts say if Hezbollah escalates its attacks, it will be a game of numbers between the two sides.
And it's uncertain whether Israel's Iron Dome will be able to "keep up".
Cracking the Iron Dome
The Iron Dome is the key tool in Israel's air defence network.
It was designed to fend off short-range rocket and missile attacks from neighbouring militant groups.
The system uses sophisticated radars to detect incoming projectiles, then fires missiles to destroy them in mid-air.
Recent videos have shown the system in action, with streaks of light illuminating the skies before rockets burst into flares.
There are 10 Iron Dome batteries strategically placed across the country, providing city-sized coverage against rockets with ranges of between 4 and 70 km.
Marcus Hellyer from Strategic Analysis Australia said Israel had created a situation where it could defend itself without needing to invade Lebanon and Gaza, where Hezbollah and Hamas are respectively based.
That strategy had been working well, he added.
But since October 7, everything has changed.
Hamas managed to saturate the Iron Dome with thousands of rockets and drones, while gunmen stormed into southern Israel for a series of deadly attacks.
"The October 2023 attack by Hamas over the Israeli border kind of blew that paradigm out," Dr Hellyer said.
"What we're seeing at the moment with Hezbollah is a similar kind of narrative."
This week, Israel's military chief said its troops were preparing for a ground offensive in Lebanon.
And despite Western calls for a ceasefire, Prime Minister Benjamin Netanyahu said Israel would continue fighting Hezbollah with "full force".
Strikes edge deeper into Israel
Hamas militants killed about 1,200 people during the October 7 attacks on Israel, and took at least 250 hostages back to Gaza, according to Israeli authorities.
Israel responded by invading the Gaza Strip in an ongoing conflict that has claimed the lives of more than 40,000 Palestinians, according to the Gaza health ministry.
Since the Israel-Hamas war broke out, Hezbollah has been launching attacks into northern Israel.
And last Wednesday, it started intensifying its strikes, edging deeper into the country.
[map]Sirens have been ringing out across highly populated cities in northern Israel.
And in a rare attack on Wednesday, a missile fired from Lebanon came flying towards the economic centre, Tel Aviv.
Israel said it intercepted most of the hundreds of projectiles fired from Lebanon.
But damage from a rocket strike was reported in the seaside city of Haifa, the cultural and economic capital of northern Israel.
Stephan Fruehling from the ANU's Strategic and Defence Studies Centre said the Iron Dome was very effective, but no system was perfect.
"Some missiles will always get through," he said.
"It's a game of numbers."
And even if the Iron Dome intercepts rockets, whatever is shot down from the sky is going to fall somewhere.
Enough rockets to 'swamp' systems
One of Hezbollah's key strengths is its large supply of missile systems and battlefield rockets, many of which are supplied by Iran.
It is believed to have stockpiles of upwards of 200,000 rockets, according to a March report from the Center for Strategic and International Studies (CSIS).
Dr Hellyer said Hezbollah had been stockpiling enough rockets to compromise the Iron Dome and cause damage to Israel's cities and infrastructure.
And many of them were cheap, unguided rockets that could hit anywhere.
"If Hezbollah fires off a whole bunch of rockets, they will swamp Israeli's missile defence system and some will inevitably get through," he said.
"If you aim them into the cities, like Tel Aviv, just by random effect, they will sooner or later start landing on buildings and causing casualties."
More powerful missiles on hand
Hezbollah says it had recently begun using Fadi 1 and Fadi 2 missiles for the first time in the conflict.
The more powerful Iranian short-range missiles are equipped with about 500 kg of explosives, with the ability to launch at a range of about 190 km.
The group said it had also used a ballistic missile for the first time, launching a Qader-1 to target the headquarters of the Mossad intelligence agency in Tel Aviv.
The missile was intercepted by the IDF, but military analysts say it was an indication of Hezbollah's capacity and the potential for further escalation in the Israel-Hezbollah conflict.
Professor Fruehling said even if more powerful missiles were destroyed by air defences, they could inflict a lot of damage due to their size.
"If you have fairly powerful missiles, you can shoot them at a very high trajectory so they come very fast and almost vertical," Professor Fruehling said.
"In which case, you may destroy the missile warhead [but] there will still be kinetic damage."
Hezbollah also has access to longer-range missiles, Professor Fruehling says.
The IDF has justified its deadly strikes across Lebanon by claiming it was targeting weapons storage facilities and infrastructure used by Hezbollah.
Prime Minister Benjamin Netanyahu has said Israel was attacking the group so it could return its displaced citizens to the north.
"We are continuing to strike Hezbollah with full force, and we will not stop until we reach all our goals — chief among them, the return of the residents of the north securely to their homes," he told reporters ahead of a UN general address last week.
Escalation by numbers
Hezbollah has signalled it is not seeking to widen the conflict, but has warned it has used only a small part of its capabilities so far.
Professor Fruehling said so far, Hezbollah's attacks were causing "less destruction, more disruption", but it was hard to know if they were deliberately withholding or not.
One of the advantages of the Iron Dome is that it uses cheap missiles, so Israel was likely to have a lot of them in stock, Dr Hellyer said.
But if Hezbollah was showing restraint and strikes escalated, Israel may end up in trouble.
"Hezbollah has had plenty of time to stockpile thousands and thousands of rockets," he said.
"So the question is, 'how many Iron Dome missiles does Israel have?' They'll have a lot, but you wonder how long they can keep up."
If Iran gets directly involved, then threats will become larger and more significant.
In April, Iran launched an attack on Israel unlike anything the world had seen.
Iran is also expected to keep resupplying Hezbollah "quickly", according to a report by the CSIS.
It added that Iran's relationships with Syria would facilitate the weapons pipeline.
