Hezbollah is a party that represents the Shiite population in southern Lebanon, they were not imported. This population was under direct Israeli occupation from 1982 to 2000. Hezbollah was formed to specifically combat this occupation and it won. Israel tried in 2006 to flex its muscle and had its nose bloodied so instead, to save face, opted to bomb the snot out of the undefended Christian north.
Israeli PM to Palestinian President Abbas: We must fight terror together (Haaretz)
from the article: MESS Report / Can Israel fend off a Hezbollah armed with Syrian rockets?