CNN reported that the US expressed concern to its ally Israel in the context of the country's plan to transfer military resources from the southern Gaza Strip to the north, bordering Lebanon, in preparation for a ground and air attack on its neighbor. A US official said: "We assess that at least some Iron Dome batteries will be overwhelmed."

Hezbollah has a large arsenal of missiles, rockets and unmanned aerial vehicles (UAVs) that are more advanced and more destructive than Hamas’s weapons, senior US officials said. The Israel Defense Forces (IDF) estimates Hezbollah has about 150,000 missiles and rockets, including thousands of precision-guided ones. So a large-scale attack using mainly advanced missiles by Hezbollah could pose a challenge to Israel’s defenses.

Earlier this month, Hezbollah released footage of its drone damaging an Iron Dome battery at a base in northern Israel. It was the first time the system had been hit, according to Israeli media. The IDF said there was no damage to the system, but expressed surprise that Hezbollah was able to carry out such a sophisticated attack.

Hezbollah also recently released a nine-minute video showing UAVs flying over a series of sensitive military sites in several Israeli cities. A US official admitted that in the event of a full-scale conflict, Israel would need to replenish Iron Dome’s ammunition and deploy other types of defense systems.

Iron Dome is Israel's most famous air defense system. It is the foundation of Israel's defense system and the US government has spent more than $2.9 billion on the program. According to the Israeli manufacturer Rafael Defense Systems, Iron Dome has a 90% success rate in intercepting incoming missiles. However, the system has limitations, such as being only suitable for dealing with artillery shells or missiles launched from close range. The system's radar has a range of 4-70 km.