You may as well ask, "how did Israel start it on Friday with their missile strike when gaza has been firing rockets into Israel all week BEFORE Friday. In fact, Israel complained to the UN Sec Council that they were just ignoring the rockets hitting Israel.
It reminds me of an incident about 10 years or so ago. Muslim terrorists bombed a French synagogue. The part that was considered egregious in their press was that "passers by" who were not even Jewish were harmed.
PS: Israel did not break the hamas ceasefire. In fairness, it does seem that neither Israel NOR Hamas agreed on what the truce actually meant and both did things that the other felt was a violation. http://www.nytimes.com/2008/12/20/world/middleeast/20mideast.html?_r=1&scp=2&sq=Ethan%20Bronner%20December%202008%20gaza&st=cse
Israel and Hamas accuse each other of bad faith and of violations of the Egyptian-mediated accord, and each side has a point. Rockets from Gaza never stopped entirely during the truce, and Israel never allowed a major renewed flow of goods into Gaza, crippling its economy. This is at least partly because the agreement had no mutually agreed text or enforcement mechanism; neither side wanted to grant the legitimacy to the other that such a document would imply.
PPS: Wow. That is a lot of misinformation.
Not only were Arabs firing rockets into Israel BEFORE Israel's strike on Friday, but Israelis strike on Friday did not Kill ANY civilians (and NO Children). It killed ONLY armed combatants. And the Arabs admitted this. And their second wave of strikes after more Arab rockets also did not kill any civilians. It killed 10 more people ALL of whom were claimed as armed combatants by their terrorist group.
And what on the subject of the quantity of rockets and artillery that Israel has fired decrease back at Gaza when you consider that that date and at Lebanon and different places? 2 wrongs do no longer make an outstanding, so why is Israel exempt from bombing others, yet different international places are not allowed to the touch Israel without a huge hoohaa? Sorry, i do no longer see any distinction, killing is incorrect on the two area and if individuals desire to call me anti Semitic then do it, least i understand that i'm no longer into killing innocents international!
"Gaza" is not a monolithic entity and Hamas do not have total control over the actions of other militant groups.
These facts are not always reflected in the Israeli response, which tends to the disproportionate and collective punishment and has as usual done most of the killing and wounding - hence much international criticism.
Arabs are notorious for their treacheries, it´s part of their culture. So, it´s not a surprise they broke the treaty; they did it 17 times before - and they will do this 170 times after. What is good is that Israel finally started to understand this dirty arab game and at the negotiations put it clear: Israel will act in accord with the situation and will answer with fire to fire, and with calmness to calmness. And just an hour after the arabs´ breach of the treaty Israeli jets struck Islamic Jihad targets in Gaza. Just two years ago Israel would wait for at least 15 hours, to make sure that the attack "was not an isolated accident".
Let the arabs go on; all the same Israel will have to secure the situation in Gaza before striking Iran, and arabs actually are doing Israel a favour giving her a wonderful reason for the massive ground attack on Gaza.
My dear Jewish friend, four hours before the first rocket was launched, the Jews attacked Gaza with four fully armed helicopters killing two unarmed civilians and seriously wounding fourteen other people, many of them little children. Please, try and post the facts right next time! Thank you for sharing