[jyl]

I'm wondering if the issue isn't more Israel's willingness to commit ground forces.

Hezbollah has a huge network of deep tunnels, they've surely moved their personnel and most weapons underground by now. Israel can use all the planes it wants, but to root out Hezbollah, IDF armour and troops will have to take the towns and destroy the underground infrastructure. I haven't heard/read too much about how that is going.