It certainly wouldn’t be the first time that the Lebanese Armed Forces took American-supplied tanks and anti-aircraft weapons and drones, and then promptly began trying to kill Israeli soldiers. And no one even bothers talking about the 200 tons of US explosives that Hamas captured after they rolled the hopelessly outmatched US-trained Fatah forces in the Gaza Strip, explosives which were subsequently used against Israeli soldiers. General Keith Dayton, the man responsible for making sure Hamas was kept out of Gaza, was promptly transferred to the West Bank. There he immediately resumed providing weapons to the Palestinian Authority, because the problem had obviously been not enough security assistance.
It was in the immediate aftermath of the Gaza failure, by the by, when the Pentagon also began enthusiastically pouring weapons into Lebanon. That assistance was promptly turned against Israeli intelligence assets, more or less decimating Israel’s ability to know what’s going on in Lebanon.
So with the Israelis facing Iranian proxies to their north and south – to say nothing of Iranian nukes to their east – the US plan for bolstering regional stability was effectively “help Lebanon make Israel really, really uncertain and nervous.” When the IDF gets skittish about the Jewish State’s prospects for survival, after all – that always goes well.