You're right Fromagio, apologies for the wrong number I have given as far as the Gaza population is concerned.
On the other hand the IDF doesn't have M1 Abrams tanks but home made Merkavas.
What the IDF does to the palestinians is exactly what the PLO then and Hamas now does to the Israelis with only one difference: the official policy of Hamas is to wipe out the zionist regime while Israel does not want to wipe out anybody.
They just protect their country (then if you don't recognize it it's your problem since it exists as per UN vote) and their interests just like any country would do, even with force if necessary.
As per Israel being founded by terrorism well, you should also check your facts because its history goes well beyond what Irgun members did to the Brits talking of which were occupying a land they didn't own and even deciding for both the Arabs and the Jews about their future while setting up detentions camps for holocaust survivors in Cyprus.
To cut a long story short the world is divided into two groups: those who recognize Israel's right to exist and those who don't.
Obviously for the 7 million Israeli people this is the starting point of a constructive discussion, otherwise they have no other option but defend themselves from those who want to deny their existence.
The palestinians are in the same situation, the only problem is that they are not eager to be constructive but only destructive and they get what they want.