The collapse of a six-month Israel-Hamas calm last Friday unleashed a new wave of cross-border attacks and a spate of threats from leaders on both side about worsening violence. And although the Islamist militants called for a 24-hour halt in attacks on Monday for mediation, the region seems once again to be at the brink of another escalation over Gaza.

"We can't leave Gaza in Hamas's power" if the Islamist militants continue to fire missiles, said Israeli Foreign Minister Tzippi Livni, a candidate for Israel's premiership, on Sunday. Hamas spokesmen, meanwhile, have threatened to resume suicide bombings in Israeli cities if the Israeli Defense Forces (IDF) increase military operations in Gaza.

For all the bravado, the recent conflict is as much about domestic muscle flexing as it is about the balance of power between the Jewish state and Hamas, which has controlled the coastal strip since June, say both Israeli and Palestinian experts.

With Israel's parliamentary election campaign heating up and the Palestinians headed toward a new deterioration in Hamas-Fatah relations over Palestinian presidential polls, the conflict is being complicated by twin domestic political struggles.

The waves of rocket fire on southern Israeli towns – militants fired at least two dozen Kassam missiles on Sunday – highlights a failure of the current Israeli administration to protect citizens from the threat of short-range rockets. The lead headline in the Israeli newspaper Maariv claimed that one-eighth of Israeli citizens are within range of Hamas's rockets in Gaza.

As Israeli opposition leader Benjamin Netanyahu spoke Sunday with upset residents in the Israeli border town of Sderot – hit by rocket fire in recent days – he called on the government to go on the offensive against Hamas.

At the same time, a parliamentary surrogate from his right-wing Likud Party suggested overrunning the blighted coastal strip of 1.6 million in the same way the IDF reoccupied West Bank cities in 2002 at the height of the Intifada.

Already trailing Mr. Netanyahu in the polls ahead of the Feb. 10 vote, Ms. Livni has advocated a tit-for-tat response to rocket fire even though it risks a descent into a wider conflict, which would certainly undermine peace talks that she has helped push forward along with the Bush administration.

"It's obvious that it would be political suicide for an incumbent government to sit back while rockets are being rained down, and say 'we're restraining ourselves,' " says Shmuel Bar, a Middle East expert at the Interdisciplinary Center, a university based in the Tel Aviv suburb of Herzliya.

On the Palestinian side, Hamas is locked in a dispute with the secular Fatah Party over the Jan. 9 expiration of the term of Palestinian Authority President Mahmoud Abbas.

The president wants to extend his term in office until the rival parties can agree to hold new elections. Hamas has said they won't recognize Mr. Abbas as president after Jan. 9.

Some observers say the renewed threat of a broader fight with Israel gives leaders in Hamas-controlled Gaza leverage in ongoing, Egyptian-brokered talks with Fatah, which controls the West Bank. "This is muscle flexing to show Fatah that Hamas can disrupt relations between Israel and the [Fatah-controlled] Palestinian Liberation Organization" by using its military arm, says Meir Javedanfar, an analyst in Tel Aviv.

"Because the more there are attacks from Gaza to Israel, the more it is difficult for Israeli leaders to justify a withdrawal. By ending the cease-fire with Israel, Hamas is hoping it can force Fatah to accept its compromise for presidential elections" as well as for other disputes, says Mr. Javedanfar.

Hamas's announcement of a day-long halt to missile strikes marked an effort to give Egypt – which brokered the initial Israeli-Hamas truce – a chance to reestablish the calm.

The renewal of the violence has also stoked concern about the scarcity of currency in Gaza. Israel, which controls the sole commercial crossings into Gaza, has blocked nearly all trade save for humanitarian supplies. Several weeks ago, Israel approved the delivery of nearly 100 million shekels, but the World Bank has warned that more cash is needed to avoid bank collapses and stem the growing black market trade in Gaza.

Even though domestic political rivalries among the Palestinians and Israelis have so far helped inflame tensions on the Gaza front, the same political tensions could, over the longer term, help keep the violence in check.

A ground invasion of Gaza and wider missile attacks on Israeli cities could hurt Livni and her incumbent Kadima Party – seen as one of the moderates who support a two-state solution to the conflict – in upcoming polls. The military hawks of Likud will likely gain even more ground if violence escalates again on the border with Gaza.

Some Palestinians say Hamas's use of force is ultimately a means to force another cease-fire agreement with Israel – but a truce that it considers more attractive than the one reached six months ago.

Hamas wants a commitment from Israel to ease restrictions on cross-border trade and the passage of people at Gaza's borders. Israel's blockade of the strip has led to vast shortages of basic goods, such as flour, and shortfalls of fuel and electricity.

At the same time, Hamas won't be able to fight Israel effectively if it doesn't mend its rift first with the Fatah Party, argued Hafez Barghouti in the Palestinian daily Al Hayat Al Jadidah.

"Hamas wants to show the Palestinian public that it can get a calm and better accords from Israel than the Palestinian Authority," he wrote. "Hamas cannot convince anybody that it is interested in the escalation with Israel because to prepare for a war you have to strengthen your internal front by uniting all forces."