You are partially correct, and partly incorrect. Hezbollah, which if not Iranian controlled, is heavily influenced by Iran, is based in Lebanon. They have a strong power base by providing services to the Shia/Allawite population in Lebanon.
The Sunni and Christian populations are not thrilled by this, but there has been no appetite for another civil war, so Hezbollah has significant influence in the Lebanese government. Now however, two forces are at work: 1) Hezbollah has been severely weakened by its heavy involvement in the Syrian Civil War, Iran bled them dry to support Assad. 2) The Lebanese discontent has spilled into the streets in the form of protests.
It looks like Mr. Trump has decided to step back and see what happens next.
Hezbollah is directly controlled by Iran. Nasralla seeded independence a decade ago.
All groups are currently arming for another civil war, which Hezbollah will win.