Although on total mobilisation, Israel could field 1/2 million soldiers, the problem is that Israel has no hinterland, no resources and little hardware reserves
http://www.jpost.com/Defense/Article.aspx?id=201919In 1973, after 2 weeks of all out conflict, Israel had run out of tanks and ammunition. If Nixon hadn't over-ruled 'Killinger' and destocked the US army in W.Germany & rush flew it over, Israel would've lost.
Similarly in 2006, after a month of bombing, Israel had totally run out of bombs and aviation fuel. If Bush hadn't flown in immediately reserves, the Israeli airforce would not have been able to continue attacking the measly little Hizbollah terrorist gang!
Israel even today can only wage an all-out war for one month against the likes of Iran, Syria, Egypt, Hamas, Hizbollah, Lebanon, & even Jordan & Saudi Arabia. Barring the use of atom bombs, after that one month, it's all over ie an Israeli surrender, cease fire, or be overrun!