What did U.S. intelligence reports suggest about Israel’s capability against Hezbollah?

U.S. intelligence reports indicate Israel may struggle to win a war against Hezbollah.
There are fears that Israeli Prime Minister Netanyahu might escalate the conflict to maintain his power.
Military officials in Washington are concerned about a potential massive bloodshed, eclipsing the 2006 Lebanon War.
Hezbollah’s attacks began on October 8, concurrently with tensions on the Gaza front.

Why is this important?

The capacity of Israel to handle a multi-front conflict with different adversaries is crucial for regional stability.
The political implications for Netanyahu could influence the decision to enter or escalate a conflict, which has broader security consequences.

Claims made by a single publication:

Israel’s forces are “spread too thin” among various fronts (Israel Hayom).
Tens of thousands of Israelis displaced due to Hezbollah’s attacks since October 8 (Ynet News).
Possible Israeli military operation against Lebanon in the ensuing spring, as per “Yedioth Ahronoth” assessments (Al Araby).
Assassination of Hamas deputy chief Saleh Arouri by Israel, which might result in retaliation from both Hamas and Hezbollah (Al Araby).
Washington’s focus on diplomatic efforts to avoid a war, with Amos Hochstein mediating border demarcation (A Araby).
Israeli Security Minister Yoav Gallant threatened to push Hezbollah back beyond Lebanon’s Litani River (Al Araby).
U.S. diplomatic efforts by Amos Hochstein may aim to de-escalate Israel-Lebanon tensions (Al Araby).
The Washington Post reflects growing fear within the American State Department and other government sections of further escalation in the Middle East (Israel Hayom).
The escalation came after a significant Hezbollah attack on an IDF base and IDF’s intensified bombings in Lebanon, attacking Hezbollah terror organization headquarters (Israel Hayom).
An estimate of Israeli casualties and Lebanese infrastructure damage was provided (Al Jazeera).

Sources: