It is a bit of both. Since overturning its objection to Lebanon's political system at the end of the civil war, it has become an important player in Lebanese politics. Its future depends greatly on its ability to retain support among Lebanon's Shiite community, irrespective of foreign backing.
At the same time, Hezbollah answers to Iran's supreme leader, Ayatollah Ali Khamenei – the group's ultimate source of religious authority and guidance. "[Hezbollah] fluctuates between both being an indigenous Lebanese party and, when needed, a proxy militia of Iran," Mr. Ranstorp told the Monitor in 2009.
Hezbollah is also committed to the regime of Bashar al-Assad in Syria, which has supplied it with arms and support over the years. The group has stood by Mr. Assad during Damascus' violent uprising over the past year that has left more than 7,000 dead.
Iran has also played an instrumental role in building up Hezbollah's military capabilities over the years, which enabled the group's impressive military wing to oust Israel from south Lebanon in 2000. It also fought the Israeli army to a standstill in the summer of 2006 – a war sparked by Hezbollah's abduction of two Israeli soldiers.
For Iran, Hezbollah's military strength serves as an important deterrent to any potential US or Israeli plan to destroy Iran's nuclear facilities. If they strike Iran, the thinking goes, Iran could turn to Hezbollah to attack northern Israel.