With every blast that propels another rocket from Gaza toward Israel, a loud Palestinian cheer goes up.
They cheer outside Shifa Hospital in Gaza City as a rocket blasts off from a location uncomfortably near the hospital itself, even as the people gathered there await the inevitable retaliation from Israel and the arrival at the hospital of new patients.
They cheer at the Hamas border post near the Erez crossing separating Gaza from Israel when a rocket is launched 200 to 300 metres away, even though Hamas itself is not firing any rockets and officially opposes the launchings.
So when Zuhair al-Qaissi, head of the Palestinians' Popular Resistance Committees (PRC), was assassinated Friday afternoon by a rocket launched by an Israeli aircraft, Hamas had no choice but to let the PRC and the Islamic Jihad group respond with rockets of their own. To do otherwise would have been seen as weak.
That Israeli "targeted killing" triggered in the past three days the most intense exchange of fire since the 2008-2009 Israeli war on Hamas in Gaza, leaving at least 18 Palestinians dead and hundreds of thousands of Israelis taking shelter in bunkers throughout southern Israel.
People cheer in Israel too when their Iron Dome anti-missile batteries intercept incoming Palestinian rockets headed toward populated areas. And they cheer when Israel television shows aerial videos of dark Palestinian silhouettes setting up and preparing to launch a rocket from the back of a pickup truck, only to be snuffed out in a grey-black cloud that follows the direct hit of an Israeli missile.
In the battle for rocket supremacy there is no contest. Israeli rockets, mostly fired from manned aircraft, have killed the 18 people, most of them militants, and wounded several others. The more than 100 Palestinian rockets that landed in Israel wounded four Israelis, one seriously.
One Palestinian Grad rocket fired from Gaza hit a school Sunday afternoon in Beersheva, but no one was there.
While tens of thousands of Israeli school children stayed home in shelters Sunday, it was school as usual for Palestinians in Gaza. Ayoub Assalya, 12, had just set out for school Sunday morning in Jabalya in the northern Gaza Strip when an Israeli missile struck and killed him.
In reporting the assassination of Mr. al-Qaissi late on Friday, Israeli officials said he was in the final stages of preparing an attack on Israel and his killing was in order to foil an immediate threat. Yet Israel must have known for some time that it was going to find that immediate threat on Friday, since Israel's southern military command deployed the Iron Dome batteries and filled the area around Gaza with a large number of unmanned observation aircraft well in advance, knowing full well the kind of response the killing would trigger.
Indeed, Defence Minister Ehud Barak acknowledged that details of the PRC plan were not entirely clear. "One might guess, judging by his [Mr. Barak's] statements that this operation was more about deterrence," wrote Ofer Shelah, in the Maariv newspaper, "and was geared to send the message that anyone planning terror attacks of that kind would be punished immediately and in cash."
Speaking Sunday at an Iron Dome location in southern Israel, Prime Minister Benjamin Netanyahu said: "We shall strike anyone who wants to strike us. Anyone who tries to act and anyone who actually causes harm – we shall strike him."
Mr. al-Qaissi was not the first Palestinian commander assassinated by Israel – far from it. He was the fourth PRC leader killed in the past six years; he'd been elected just last August following the killing of his predecessor, Kamal al-Nairab. In that case, Israel Defence Forces launched a reprisal attack on Gaza following the killing in August of eight Israelis near Eilat in a operation Israel said had been executed by the PRC.
That assassination led to four days of battle also led by the PRC and Islamic Jihad, during which 160 rockets and dozens of mortar shells were fired at southern Israeli cities.
Egypt attempted this past weekend to broker a ceasefire between Israel and the warring Palestinian factions. But both Islamic Jihad and the Popular Resistance Committees have said they are not interested in a cessation of hostilities unless it means an end to Israel's practice of assassination.
Israeli officials, however, say the lesson they learned from last August's Eilat attack, is not to strike after such an attack but before it.
Editor's Note: An earlier version of this story misspelled the first name of Zuhair al-Qaissi. This version has been corrected.