Some Israeli lawmakers, including former military chief of Staff Shaul Mofaz, are pressing the government to authorize the assassination of Hamas leaders in the Gaza Strip amid an escalation in clashes on the Jewish state's southern border.

There's already growing speculation that Israeli Prime Minister Binyamin Netanyahu is leaning toward unleashing a new invasion of the Palestinian coastal enclave, along the lines of the massively 22-day Operation Cast Lead launched in December 2008.

A major problem is that either military option, in response to an escalating series of rocket and mortar barrages from Gaza in recent weeks, could have serious political ramifications.

The most dangerous would be to incense Egypt's new Islamist government and place Israel's landmark 1979 peace treaty with its southern neighbor in deep jeopardy. The treaty, the first between Israel and its Arab foes, has been the centerpiece of Jewish state's security policies for more than three decades.

The rocket barrage that began Saturday eased by Tuesday but Israeli Defense Minister Ehud Barak declared when he inspected the border zone, "It's still not over."

After meeting military commanders, including the battle-seasoned head of Southern Command, Maj. Gen. Tal Russo, Barak said that Palestinian militants "are absorbing heavy blows in Gaza as a result.

"This clearly isn't over and we'll decide how and when to act the minute there will be a need to do so."

He declined to elaborate but Israeli anger and anxiety is mounting, not just about the growing rocket threat from Gaza but the much wider, and infinitely more perilous, threat from more destructive ballistic and other medium-range missiles from Iran, its ally Syria and their powerful proxy in Lebanon, Hezbollah.

Israeli military planners say these adversaries could sustain a massive and unprecedented bombardment of Israeli cities involving up to 200-300 missiles a day for as long as two months.

Officials have said this multi-front conflict, which would target population centers to a degree unseen since Israel was founded in 1948, would probably result in an estimated 500 civilian fatalities.

But many suspect the death toll will be far, far higher and the option of pre-emptive strikes to curtail such an eventuality, is widespread, in particular against Iran's nuclear program which Netanyahu views as an existential threat.

Israel's military and intelligence services have long engaged in assassinating the leaders of countries and organizations attacking the Jewish state but this carries great risks and dead leaders have always been replaced.

The Jerusalem Post observed that various political figures from several parties are "explicitly or implicitly calling for returning to targeting Hamas leaders as a way of returning deterrence and quiet to the south."

Most Israelis have no qualms about killing the leaders of militant Palestinian groups. Indeed few of Hamas' original leaders are still alive. But the Post questioned whether killing Hamas' political leaders now is legal.

The daily noted that U.S. forces used decapitation operations to eliminate Iraqi leadership cadres in the 1991 and 2003 wars.

Israel halted assassinating Hamas political chiefs amid the global outcry after Operation Cast Lead.

But the Post said that "real confusion arises regarding Hamas leaders who are sitting in an office somewhere nowhere near the battlefield, who do not participate at all in an attack, but may have ordered the attack or could only be vaguely connected because they are leaders of Hamas and known Hamas' policies against Israeli civilians."

Israel used to be widely criticized for its "targeted killings" of top Palestinian militants. But the Post concluded that al-Qaida's suicide attacks on the United States Sept. 11, 2001, "created a new paradigm."

On Monday, Israelis got a reminder of the many assassinations carried out over the years by the Mossad intelligence service and the army's elite Sayaret Matkal unit.

Barak commanded the unit in the 1970s. Netanyahu served under him. They both took part in rescuing hostages aboard a hijacked Belgian Sabena airliner at Tel Aviv airport May 8, 1972. All four hijackers from Palestinian Black September were killed.

The reminder was a television documentary that showed how in the 1970s the Mossad, busily engaged in trying to undermine Iraq's anti-Israel Baathist regime, tried to assassinate Saddam Hussein with a book bomb.

Saddam didn't open the package but a high-ranking official did and was killed.