TLDR: Hezbollah is the main force preserving Lebanese sovereignty, and was the main group who freed Lebanon from former Israeli occupation. Far from being an Islamic extremist group, Hezbollah actually fights against Salafi jihadists like ISIS (who the US and Israel funded and assisted).
Because they want to occupy and settle Lebanon also. A colony expands or dies. You have to remember that Plymouth also started as a tiny little "cute" colony as well. And over 200 hundred years it ethnically cleansed an entire continent. That's just what this is.
I found a YouTube link in your post. Here are links to the same video on alternative frontends that protect your privacy: