Israel's government's unwillingness to do what's necessary to stop the bombardment of Sderot exhibits all its warts.

Sderot is under constant bombardment from Hamastan.  The only residents left are those unable to run away.  The only thing that can stop the rain of Kassams is for Israel's army to go back into Gaza, eliminate Hamastan as a political entity, seize the missiles and their launchers, and kill those who have been firing them.  The back-to-Gaza operation has been talked about for months.  Why isn't it happening?
Israel's legal system will never permit the IDF to do the job as it should be done. If Israel's army must attack Gaza, Israel's judges and jurists want the soldiers to walk up to enemy held buildings, knock on the door, and yell, "any women and children in here?" Playing by these rules, Israel could take massive casualties and, as in Lebanon, not even win.

The question gets sharper when one considers the future.  According to Israeli military authorities, Hamas is about to cross two technological thresholds.  One is to improve the range of its missiles to about 10 miles.  This means it will be able to hit towns in Israel from anywhere in the Gaza Strip.  The other is the ability to store missiles for months at a time without their rocket fuel or explosive warheads deteriorating; today kassams have to be fired off soon after they are manufactured.  Once these thresholds are passed, Hamas will be able to store hundreds of kassams and, in the event of an Israeli attack, rain them on Israeli towns from Ashdod to Netivot, reproducing around Gaza the conditions of Israel's northern region during the Second Lebanon War.

So why doesn't Israel move first?

The answer illuminates a lot that is wrong about Israel's present system of government. 

One element of the answer has to do with Israel's legal system.  A couple of months ago Israel tried to do a simple thing:  Cut the supply of fuel and electricity to Gaza, so as to put pressure on the Hamas regime.  The Attorney General, Menahem Mazuz, intervened.  Can't do that, he said.  It's against the civil rights of the people in Gaza.

Now fighting in Gaza will be tough:  It means going into built-up, urban areas, laced with mines, antitank missiles and machine guns, and thousands of well-trained defenders.  To do the job you need to use aircraft and artillery—really use them; in principle you never want your own troops to assault an enemy-held building while it is still standing, only after your planes and cannon have knocked it down and pulverized the rubble and whoever is in it.  Israel's legal system will never permit the IDF to do the job as it should be done.  If Israel's army must attack Gaza, Israel's judges and jurists want the soldiers to walk up to enemy held buildings, knock on the door, and yell, "any women and children in here?"

Israeli military authorities estimate that an assault on Gaza would cost a hundred fatalities.  That sounds to me like a serious underestimate.  Playing by the Mazuz rules, Israel could take far more casualties and, as in Lebanon, not even win.
The last thing Barak needs is to be held responsible for a bloody, losing fight in Gaza. That would end his second political career before it got properly started. And what could be more important than Ehud Barak's political ambitions?

The second element of the answer has to do with the quality of Israeli politicians.  Ehud Barak is Israel's defense minister.  When he entered the office a few months ago, he thought he was on the inside track to the Prime Minister's office.  It turns out he was wrong.  He isn't much more popular than Ehud Olmert is.  The last thing he needs is to be held responsible for a bloody, losing fight in Gaza.  That would end his second political career before it got properly started.  And what could be more important than Ehud Barak's political ambitions?

Barak was skeptical about Olmert's Annapolis adventure from the beginning.  Then he himself accompanied Olmert to Annapolis, and suddenly became a convert.  "We can't attack in Gaza," he leaked to the press, "that would prejudice our wonderful opportunities for peace."  I find it hard to credit the idea that Barak suddenly discovered, at Annapolis, an Arab world yearning for peace and a Palestinian leadership capable of doing anything to bring it about.  But it makes a wonderful excuse not to get into that losing fight around Gaza.

Of course, such an approach is extremely shortsighted.  In a matter of weeks or months Hamas will start shooting missiles at more Israeli cities like Ashkelon, Ashdod and Netivot—only a few a day, of course, enough for Ehud Barak, safely ensconced in his Tel Aviv office, to consider bearable, while for the residents of the targeted cities life slowly becomes unbearable.  If Israel attacks, then the missile strikes will escalate to a hundred a day, just like in the Lebanon war in 2006.
The Olmert-Barak cabal needs to be swept out of office. And Israel needs to trash its legal system and replace it

All this shows the magnitude of the change Israel needs.  The Olmert-Barak cabal needs to be swept out of office, to be replaced by a leadership whose first priority is to defend the lives of Israeli, not Palestinians, civilians and soldiers.  There is more, however.  Put simply, Israel needs to trash its legal system and replace it: sweep  judges and jurists who won't let Israel fight to save its citizens' lives out of office and replace them with others who will.  For that one needs brave and determined political leaders.