When you give Hamas even a slight pass and say Israel should sit down at the table while the attacks continue (a ceasefire is a different matter altogether), you suddenly have turned every humanitarian-minded foreign policy and global political mind from being your ally to your enemy, because in the grand political calculus that sets an awful precedent that will destabilize any potential peace deal. If Hamas can win concessions by targeting civilians, there is no reason for them to ever stop. And they won't. If you think for a single solitary second that Hamas would be content and never hit at Israel again with a functional two-state solution along the 1967 borders if we could have it set up tomorrow, you're delusional. The same goes for Likud's expansionist bull****. But you can't get rid of Likud without getting rid of Hamas first. Likud exists and holds power because organizations like Hamas exist; without them, Israeli moderates run the show and Likud is forced back to the fringes where they frankly belong.
As I've said from my first comments: the problem is Hamas, and/or movements like it.
Quoting myself, because it seems the other three people who posted since didn't bother to read it.
All of your arguments are great. They demonstrate - admirably - that Israel aren't "the good guys." Of course, I haven't been saying Israel ARE the good guys, so I'm not entirely sure why you're bothering to try to make that point in my direction.
What I have been arguing - repeatedly - is that if one supports a long-term peace agreement between Israel and the Palestinian territories, one cannot then argue that Israel should sit down and negotiate with Hamas while attacks are ongoing against its civilian population (and no, Dark, the US has never done this and no, kara, neither did the UK with the IRA). A ceasefire, however temporary, changes that calculus, regardless of whether it is broken periodically on single occasions. Nowhere have I said that the condition of negotiation should be all attacks out of Gaza stop permanently never to happen on occasion during the negotiations because I know full well that is unrealistic. The idea that Hamas, which is at least somewhat organized militarily, stop and actively try to prevent additional attacks while a ceasefire is in effect is.
I have never claimed Hamas is not the government of Gaza. Rather, I have repeatedly pointed out that Hamas was elected as the government of Gaza and now runs the territory undemocratically entirely by force, with a minority of popular support. They also happen to be a terrorist organization whose ultimate goals mirror that of the Muslim Brotherhood and, most recently, IS. These are all very good reasons to minimize Hamas' influence on the peace process to the greatest possible extent. A two-state solution with Hamas at its present level of influence (most of which is due to force projection) is untenable, because, again, their goals are incompatible with a long-term peace process.
Vega brought up the choice of Israeli targets. While Israel has predominantly hit at fighting forces, rocket launch sites, and personnel staging areas (which have also included some supposed safe zones due to Hamas hiding in them, an action I doubt believe to be excuseable regardless), they also hit at critical infrastructure... though not consistently and typically not enough to destroy it outright (while Gaza's sole power station is damaged, it's not a smoking crater so there is some restraint being realized). There is a tactical and political purpose to this, and it's to make Gaza as a whole pay for the actions of Hamas. Brutal political calculus? Absolutely. Potential war crime? Maybe. Effective? Definitely. Hamas does not command popular support, and more and more Gazans are wishing for a return of the PA government.
I want to see a long-term peace agreement in the region as or more badly than anyone. However, Hamas is a long term security threat to the stability of the entire region, and an even greater one where they operate in a state without blockades, controls, and with an effectively unarmed government of the PA as their sole opposition. Want to see Palestine turn into a fundamentalist, rights-abusing caliphate? Negotiate a two-state solution with Hamas at its current level of power. They'd take Palestine by force of arms in less than a year, and we'd be back worse off than where everyone in the region started.