A barrage of missiles this week exchanged between Israel and Hezbollah in Lebanon have made U.S. officials increasingly concerned that the escalation could spiral the war-torn region into a broader conflict between the U.S. ally and Iranian-backed militia.

Since Oct. 7, the Biden administration has been furiously working behind the scenes to lower the chances of a conflagration that could draw in the U.S. or put at further risk U.S. troops who are in the region in Syria, Iraq and Jordan. Amos Hochstein, a top diplomatic adviser to President Biden, is headed to Israel Monday to work on de-escalating the conflict, according to a U.S. official.

U.S. officials expressed concern about several scenarios. Some told CBS News they interpret the recent deeper strikes by Israel inside of Lebanese territory as preparing the battlefield for a sweeping assault by Israel Defense Forces. Hezbollah has responded by launching larger rocket attacks into Israel. These officials are increasingly concerned that Israel will start a war against Hezbollah in Lebanon that it cannot finish without American support.

Other U.S. officials tell CBS that their apprehension is focused on Hezbollah and described a scenario in which the volume of the rocket strikes into Israel could result in unintended consequences that trigger an event Israel feels compelled to respond to and which could then result in an unintended war. 

Inside Israel, the Hezbollah threat has become a potent political issue because many Israelis who evacuated their homes in the north of the country remain displaced. Following the Oct. 7 attack by Hamas in Israel and the launch of the war in Gaza, many residents of northern Israel and southern Lebanon left their homes out of concern that they were living in an area that could soon become a battlefield.

The increased tit-for-tat cross border exchanges between Israel and Hezbollah make it harder for the U.S. to ease tensions in the region, particularly if the Biden administration's efforts to broker a hostage and cease-fire deal in Gaza founder. The administration views the cease-fire talks and the Israel-Hezbollah tensions as intertwined. 

A senior Biden administration official told reporters in Italy Thursday, "The most important thing about the hostage release and cease-fire deal that's on the table now is that if it's achieved, it can have an impact in the north [of Israel], so that is an opportunity for us to be able to bring this conflict to a full close."

The official also said that as a part of any cease-fire deal, there must be "specific arrangements in Lebanon on the border." 

"There has to be an agreement that allows Israelis to return to their homes in the north with security guarantees that it is not Oct. 6 of Hezbollah … sitting right on the blue line."

The recent Israeli strike that targeted and killed commander Taleb Abdullah, one of the highest-ranking members of Hezbollah, has triggered reprisals. Public events mourning Abdullah are expected in the coming days.

Unlike the surprise attack by Hamas in October, a possible war with Hezbollah in Lebanon is something the Israeli military has been gaming out for years, according to U.S. officials.

Israeli troops in the northern command are training in brigade-sized units but are not yet in position to begin an assault, a U.S. official said.

In:
• Israel
• Hezbollah
• Lebanon

David Martin

David Martin has been CBS News' national security correspondent, covering the Pentagon and the State Department, since 1993.

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