The devastating air assault on the Gaza Strip which began on 27 December, and the ground invasion that followed, are the latest stages in the unequal war between the state of Israel and the Islamic Resistance Movement, better known by the acronym Hamas. The onslaught has so far led to the deaths of more than 600 Palestinians, many of them children, including those killed in an air strike on the UN-run al-Fakhura school in the Jabaliya refugee camp. Since Hamas's unexpected victory in legislative elections in January 2006, Israel has been attempting to loosen the organisation's grip on the Palestinian territories. Although the elections were widely acknowledged to be free and fair, neither Israel nor any of its western allies was prepared to recognise a Palestinian Authority run by what they regard as a terrorist organisation. A civil war broke out between Hamas and Fatah, Israel's so-called partner for peace which runs the PA, and in June 2007, Hamas fighters ousted their rivals from Gaza. The Israelis responded by imposing a blockade on the coastal territory, and Fatah began attempting to excise Hamas from the West Bank.

As Edward Platt reported in the New Statesman recently ("Israel v Hamas: the war that can never end", 3 November 2008), Hamas derives much of its support from the network of charitable institutions it runs and on which many Palestinians depend for survival. Having outlawed Hamas's executive and military wings, the PA and the Israeli army began to close down the schools and orphanages, claiming that they had become breeding grounds for a new generation of terrorists and a means of raising funds for terrorist activities. Hamas called it a "declaration of war on the poor and the needy". It was.

In Gaza, the campaign proceeded by even blunter means. At the end of February, Israel launched a five-day strike intended to put an end to the barrage of Qassam rocket fire that various paramilitary groups, including Hamas's military wing, had been directing from Gaza into southern Israel. Like the current campaign, it ended with incursions by the Israeli army, and resulted in the deaths of many non-combatants; according to the Palestinian human rights organisation al-Mezan, 65 of the 119 Palestinians killed were civilians.

"Operation Warm Winter" did not immediately achieve its aim of ending the barrage, but a ceasefire came into effect in June and held for six months. As usual, both sides blame the other for breaking it, though the first recorded incident of the latest stage of the war occurred on 4 November, when Israeli special forces entered the Gaza Strip and killed six militants. On 5 November, Hamas resumed its rocket attacks and Israel increased the severity of the blockade, which it had never fully lifted, and which has turned Gaza into a kind of open prison, a place of misery and hopelessness. Supplies of food, fuel and medicine were cut off and it was plain that a humanitarian disaster was developing.

In the circumstances, that Hamas continued to fire rockets into Sderot and other towns in south-west Israel was a grotesque and pointless provocation. Yet it could claim, with some justification, that it was only responding to the greater Israeli aggression of the blockade, and its defiance may play well to a section of its domestic audience. But the majority of the population that it claims to represent has suffered terribly as a result. Public opinion in Israel demanded a response to the relentless Qassam attacks that had led to the deaths of 24 of the country's citizens, and, predictably, it has come in time - and with George Bush still nominally in power in the US - to restore the prospects of Tzipi Livni and Ehud Barak, foreign minister and defence minister in the current coalition government, who will lead Kadima and Labour in next month's elections.

Yet it is hard to see how Israel will benefit from its instinctive reversion to force, grotesquely disproportionate in this latest war. It is also hard not to see this invasion of Gaza, as well as the invasion of Lebanon in 2006, as proxy wars in the larger conflict with Syria and Iran.

The campaign is unlikely to damage Hamas as much as Israel seems to hope - its military wing need only retain a rudimentary fighting capacity to claim a victory of sorts, and because of its willingness to resist the invasion, it may yet emerge from the conflict with its status enhanced. It is hard to predict what Hamas will do next; its pronouncements are often contradictory, yet it seems to have accepted the idea of establishing a Palestinian state on pre-1967 borders. However, with prospects for a two-state solution rapidly receding, such openings should be exploited to the full, and we must hope that President-elect Obama has a broader grasp of the needs of the region than the callous and inadequate administration seeing out its last days in office.

When the fighting ends, international pressure must be brought to bear to ensure the blockade is lifted and the next truce must be monitored with greater vigilance than the last. Yet, so long as Israel remains committed to Hamas's destruction, and Hamas continues to strike against Israeli civilians, there will be no lasting peace. It may be unpalatable to deal with a group that endorses suicide bombing and which is virulently anti-Semitic, but Israel, and its sponsor, the US, must acknowledge Hamas as the democratic choice of the Palestinians and seek grounds for compromise. In the long run, negotiations will provide a more effective and infinitely more humane way of protecting Israeli citizens than attempting to batter the Gazans into submission.