Why has the US and Israel’s war with Iran spilled into Lebanon, nearly a thousand miles away? On Ian Explains, Ian Bremmer looks back at how Iran transformed Hezbollah from a small Shia militia into one of the world’s most powerful non-state military forces. Founded after Israel’s 1982 invasion of Lebanon, Hezbollah gave Tehran a heavily armed proxy on Israel’s northern border, and a way to confront Israel without fighting the war itself.