the reasons behind the attack are more complex..
essentially it is a proxy war with The Iranians and Syrians supplying Hizbollah, and the US helping Israel on the other side.
According to Seymour Hersh latest NewYorker article, an intercepted Hamas communique, stated that since the ceasefire by Hamas since it came to office was achieving nothing it was time for action.
It looks like both sides have been preparing for a fight.
On the US and Israeli side, it is a test in possible preparation for knocking out Iranian nuke sites, from the Iranian side it is a test asymetric guerrila missile defence (and judging from Israels inability to win decisively it was successful)
(see technologyreview.com missiles of august)
from Hizbollahs point of view, they come out as victors - at least in the Arab world, and with more power and popular support in Lebanon.
Although its questionable that they gained much other than widespread destruction of Lebanon.
Ultimately there are no victors though, it will probably lead to a more hardline Netanyahu govt in Israel, who will need to come up with a better response to Hizbollah.