PARIS (Reuters) - A new balance of power in the Middle East will limit Israel's ability to impose its ceasefire terms on Hamas in Gaza, but technology is compensating by curbing the Islamist militants' capacity to cause casualties in the Jewish state.
The strategic environment has changed radically since the last major armed conflict between Israel and Hamas in the winter of 2008-09, which involved an Israeli ground invasion of the Gaza Strip and ended with 1,400 Palestinian and 13 Israeli dead.
Arab Spring uprisings have brought the Muslim Brotherhood - soul mates of Hamas - to power in Egypt, Israel's southern neighbour which controls the Gaza enclave's only other border, and in Tunisia, toppling veteran Western-backed autocrats.
"Hamas has concluded that the Arab Spring gives it a number of advantages and opportunities, and it is trying to capitalise on that to change the rules of the game with Israel, and to change the relationship with Egypt," said Yezid Sayigh, a senior research associate at the Carnegie Middle East Centre in Beirut.
The changed regional balance makes an Israeli ground assault on Gaza less likely this time, and may enable Hamas to force an easing of Israel's economic blockade of the Gaza Strip, provided it does not overplay its hand, the Palestinian scholar said.
In other strategic shifts, Turkey, a major regional power, has turned vociferously hostile to the Jewish state and lent political support to Hamas, although Israel retains discreet relations with Ankara and its security establishment.
And the United States, under President Barack Obama, has embraced the Arab Spring movements and taken a less interventionist role in the Middle East, leaving regional powers largely to manage their own conflicts.
"The regional context is much different from what it was three or four years ago," said Oded Eran, a former top Israeli diplomat who is now a senior research associate at the Israel Institute for National Security Studies.
"That imposes big strains on Israel's manoeuvrability, both militarily and diplomatically."
Hamas may have felt emboldened to scale up the latest round of fighting by allowing the firing of dozens of rockets into Israel the day after a landmark visit on October 23 by the emir of Qatar that cracked Gaza's diplomatic isolation and delighted the Islamist movement, which has run the coastal strip since 2007.
That was followed in turn by Israel's assassination of top Hamas military commander Ahmed al-Jaabari in a targeted air strike on November 14, prompting further escalation on either side.
Sayigh said Jaabari had just returned from reviewing a draft ceasefire agreement drawn up by Egyptian military intelligence officers mediating with Israel.
He questioned whether Hamas had intentionally set out to generate hostilities on this scale and said an Israeli general election set for January 24 may have influenced Israeli Prime Minister Benjamin Netanyahu's decision to strike now.
Hamas has longer-range rockets than it had in 2008, some supplied by Iran and smuggled into Gaza via tunnels from Egypt. A handful have been fired at Tel Aviv and Jerusalem, the politically sensitive main Israeli population centres.
But Israel's new Iron Dome anti-missile system has intercepted dozens of rockets, while many others have been destroyed before being fired, landed harmlessly or caused minimal damage. The only three Israeli dead in the latest round of fighting were killed by a shorter-range strike on Kiryat Malachi, a southern town, 20 km (12 miles) from the Gaza border.
Without Iron Dome, the rocket fire at Israeli cities could well have caused enough casualties to stir overwhelming public pressure for a ground invasion into Gaza.
Nevertheless, the Islamist movement can boast that it has struck deep inside Israel and forced residents of Tel Aviv, Jerusalem and the southern city of Beersheva into the air-raid shelters, demonstrating its power to disrupt normal life.
SHOW OF FORCE
This show of force came at a time when the Palestinian Authority led by Mahmoud Abbas's secular Fatah movement, Hamas's bitter rival which runs the West Bank, is pressing a diplomatic campaign to gain an improved status at the United Nations.
"My assumption is that one reason why Hamas did all this was to pre-empt a victory at the United Nations next week for Abu Mazen," Eran said, using Abbas's informal name. "Hamas wanted a victory with blood that is better than a white-collar, paper victory."
How the latest round of armed conflict ends will depend crucially on the role chosen by Egyptian President Mohammed Mursi.
Mursi has already departed from his ousted predecessor Hosni Mubarak's stance by sending his prime minister to demonstrate support for Hamas in Gaza last Friday. He has also stated publicly that an Israeli ground offensive would be unacceptable.
But, Eran said, despite his critical statements and the symbolic recall of Egypt's ambassador from Israel, Mursi has been careful not to call into question their 1979 peace treaty nor to jeopardise the U.S. and IMF economic assistance on which Cairo is now more reliant than ever.
The key to a ceasefire agreement would be how far Egypt was prepared to limit arms supplies to Hamas in future and whether it would allow multinational observers in Sinai to verify that, the former Israeli diplomat said.
Sayigh said Mursi had other options to support Hamas if the conflict endured, such as encouraging Egyptian citizens to raise funds and take relief supplies into Gaza in a show of support, opening Egypt's border more generously to Palestinians and applying more public pressure on Israel and the United States.
"This Gaza conflict shows that the political balance may be more important from now on than the military balance," he said.
Obama, who has so far backed what he calls Israel's right to defend itself against rocket fire, made clear on Sunday he wants his ally to avoid a land invasion that would, judging by last time, rapidly sap Western public sympathy for the Jewish state.
Netanyahu, too, would seem to have an interest in keeping this year's Gaza operation limited, with as few Israeli casualties as possible, two months before an election that polls show he is strongly placed to win.
Hamas knows that too, and radicals in its ranks or in other Islamist groups may try to goad the Israelis into an incursion.
As always in the Middle East, a single strike that caused heavy civilian casualties could upend cool calculations and force a sudden escalation, or an early end to the fighting, before one side or the other has achieved its objectives.
Yet despite the changed strategic environment, the most likely outcome seems similar to the way Israel's limited wars in Lebanon and Gaza have ended in the last decade - a ceasefire that buys at most a few years and at least a few months' calm, with both sides expecting another round eventually.
(Editing by Alastair Macdonald)