US concerned Israel’s Iron Dome could be overwhelmed in war with Hezbollah, officials say

US officials have serious concerns that in the event of a full-blown war between Israel and Hezbollah, the Iran-backed militant group could overwhelm Israel’s air defenses in the north — including the much-vaunted Iron Dome air defense system, three US officials told CNN.

The fears, which the US officials said have also been communicated to them by Israel, that the Iron Dome could be vulnerable to Hezbollah’s vast arsenal of missiles and drones are only rising as Israel has increasingly indicated to US officials that it is preparing for a land and air incursion into Lebanon.

Israeli officials have told the US they are planning to shift resources from southern Gaza to northern Israel in preparation for a possible offensive against the group, US officials told CNN on Wednesday.

“We assess that at least some” Iron Dome batteries “will be overwhelmed,” said a senior administration official.

An Israeli official said that would be more likely if Hezbollah conducted a large-scale attack principally using precision guided weapons, which could be challenging for the system to defend against. Hezbollah has been stockpiling precision guided munitions and missiles from Iran for years, which Israel has repeatedly raised concerns about.

Earlier this month, Hezbollah released a video purporting to show a drone striking and damaging an Iron Dome battery on an army base in northern Israel. Israeli press reported it appeared to be the first documented instance of the system successfully being hit.

The IDF said it was unaware of any damage to the system. But Israeli officials have told the US they believe the Iron Dome could be vulnerable, particularly in northern Israel, and have been surprised at the sophistication of Hezbollah’s strikes to date, the two US officials said. A primary concern is Hezbollah using a large number of precision guided munitions and missiles, said a source familiar with the threat.

The Lebanese militant group also published a nine-minute video this week, purportedly taken by a drone, showing sensitive Israeli military sites in several Israeli cities.

A separate US official acknowledged to CNN that in the event of a full-blown war, the support Israel will need most is additional air defense systems and Iron Dome replenishments, which the US would provide.

The IDF declined to comment.

The Iron Dome is fundamental to Israel’s defense and the US government has spent over $2.9 billion on the program, according to the Congressional Research Service. The Israel Defense Forces said the system boasted a 95.6% success rate during a rocket salvo fired by Islamic Jihad last year so if Hezbollah did overwhelm Israel’s missile defenses it would risk Israeli military and civilian lives.

‘A very dangerous period’

The discussions come as the situation on Israel’s northern border has reached a dangerous tipping point, US officials said.

“The fact that we have managed to even hold the front for this long has been a miracle,” a senior US official said, referring to the US’ efforts to keep the Israel-Hezbollah attacks from spiraling into an all-out war.

“We’re entering a very dangerous period,” another senior Biden administration official said. “Something could start with little warning.”

The implications of a wider war between Israel and Hezbollah could be devastating, the senior US official said. Hezbollah has an arsenal of rockets, missiles and drones exponentially larger, more sophisticated and more destructive than Hamas. Most are short range rockets, but some can reach deep into Israel with precision capability. The IDF has estimated that Hezbollah has approximately 150,000 rockets and missiles, including thousands of precision munitions.

The possibility for war has continued to increase as the prospects of a ceasefire deal between Israel and Hamas have faded, the first senior US official said. If a deal is reached, then there is a parallel diplomatic deal between Israel and Hezbollah that has been negotiated by US envoy Amos Hochstein that the US believes would go into effect.

Hochstein visited both Jerusalem and Beirut this week, meeting with senior Israeli and Lebanese officials to advocate for his plan and dissuade the sides from further escalation.

But cross-border attacks between Israel and Hezbollah reached a new high last week, and Israel warned Hezbollah on Tuesday of the prospect of “all-out war” after the drone video was published.

Israeli officials have told the US, and the US agrees, that they have the resources to carry out an offensive against Hezbollah if they need to, particularly if its campaign in Rafah in southern Gaza winds down, according to officials familiar with the discussions. The IDF intends to still maintain a presence in Gaza, but its fiercest operations in the enclave would largely be over after Rafah, officials have said. Still, US officials do not believe that Israel has a tenable transition and post-war governance plan for Gaza that would ensure that the enclave does not once again fall under militant control if Israel has to shift resources toward a war with Lebanon.

US officials have not explicitly told Israel that they oppose any attack against Hezbollah, but they are warning them that their actions could lead to a greater war which the two sides don’t actually want, a US official said. Israel has made the case that it can pull off a “blitzkrieg,” but the US is warning them that they may not be able to ensure that it remains a limited campaign, the official said.

Israel ‘very serious about going into Lebanon’

During Secretary of State Antony Blinken’s recent trip to the Middle East, he told an Arab counterpart that it appears Israel is intent on launching an incursion into Lebanon, according to a source familiar with the meeting.

“It seems that they [Israel] are very serious about going into Lebanon,” the person said. The Arab official’s response to Blinken, the source added, was that Hezbollah has communicated that they will not stop their strikes on Israel until Israel stops its operations in Gaza.

Israeli officials have told the US that one of its main goals in an offensive would be to push Hezbollah back, creating a buffer zone between Israel and Lebanon and allowing the tens of thousands of Israelis who have been forced out of their homes in the north because of the cross-border attacks to return.

If war is averted and Hochstein’s plan goes into effect, it would similarly see Hezbollah pull back around six miles, or ten kilometers, away from the border. But in order to prevent a return by the group in the future, Israel may want to further destroy Hezbollah’s infrastructure in the area.

The US has worried for months that Israel could launch an incursion, with intelligence assessments earlier this year indicating that it could come by early summer. US officials have also rebuked Israel for its strikes that have hit the US-backed Lebanese army, rather than Hezbollah targets.

US officials assess the Israeli government is under growing domestic political pressure to address the situation in the north because of how many Israelis have been forced to flee their homes.

Israeli Defense Minister Yoav Gallant held an operational assessment at the IDF’s Northern Command on Wednesday, where he said, “We are achieving readiness on land and in the air.”

“We have an obligation to change things in the North, and to ensure the safe return of our citizens to their homes, and we will find a way to achieve this,” he said, according to his spokesperson.

Allies are also deeply concerned about the potential that a full-scale conflict between Israel and Hezbollah could draw in other proxy groups, multiple sources familiar told CNN. US officials are particularly worried about the thousands of US troops in the Middle East who could once again be targeted by Iran-backed proxy groups if Hezbollah, Iran’s most formidable proxy group, and Israel go to war.

There are additional concerns about how willing other regional players would be to come to Israel’s support and defense if Israel initiates a greater conflict, explained one of the officials.

Hezbollah chief Hassan Nasrallah said on Wednesday that if war is “imposed” on Lebanon then Hezbollah will fight with “no rules and no ceilings.” He also said nowhere would be safe from Hezbollah attacks in the event of a war, including targets in the eastern Mediterranean. Over 1,000 US troops are stationed in the eastern Mediterranean now in support of the US military’s humanitarian pier operation.

Nasrallah also warned on Wednesday that Hezbollah could target Cyprus if the country allowed Israel to use its airports and bases to strike Lebanon.

Hezbollah’s ground force is also larger than Hamas’, with an estimated 40,000 to 50,000 fighters, according to the Congressional Research Service. Nasrallah on Wednesday said the number of fighters Hezbollah has actually “far exceeded” 100,000. Many, including their elite Radwan Force, have years of experience fighting in Syria on behalf of the Assad regime.

Despite a state of conflict existing between the two neighboring states, the Israel-Lebanon border has been the quietest for years since the end of the 2006 war, with only occasional cross-border fighting that ended relatively quickly. But Hamas’ October 7 attack radically changed the status quo between Israel and Hezbollah.

Rocket launches and drone attacks from Hezbollah have become a new reality in northern Israel, and the IDF carries out numerous strikes in southern Lebanon on a daily basis. The current hostilities, which could have started a war before October 7, have become all too routine, even as the US continues to say that neither side wants a wider conflict.

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