Ariel Sharon, who died on Saturday after eight years in a coma, was one of Israel's most iconic and controversial figures. His long and chequered career as a soldier and politician largely revolved around one issue: the conflict between Israel and its Arab neighbours. As a soldier he was involved at the sharp end of this bitter conflict. As a politician he became known as "the Bulldozer" on account of his contempt for his critics and his ruthless drive to get things done. Sharon was a deeply flawed character, renowned for his brutality, mendacity, and corruption. Yet despite these flaws he holds a special place in the annals of his country's history.

Sharon was an ardent Jewish nationalist, a dyed-in-the-wool hardliner, and a ferocious rightwing hawk. He also displayed a consistent preference for force over diplomacy in dealing with the Arabs. Reversing Clausewitz's famous dictum, he treated diplomacy as the extension of war by other means.

The title he chose for his biography aptly summed him up in one word – Warrior. Like Shakespeare's Coriolanus, Sharon was essentially a fighting machine. His critics denounced him as a practitioner of "gun Zionism", as a perversion of the Zionist idea of the strong, fair-minded, and fearless Jew. To the Palestinians Sharon represented the cold, cruel, militaristic face of the Zionist occupation.

In 1953 Major Sharon committed his first war crime: the massacre of 69 civilians in the Jordanian village of Qibya. In 1982, as minister of defence, he led Israel's invasion of Lebanon in a war of deception that failed to achieve any of its grandiose geopolitical objectives. A commission of inquiry found Sharon responsible for failing to prevent the massacre by Christian Phalangists of Palestinian refugees in Beirut's Sabra and Shatila camps. This verdict was etched on his forehead like a mark of Cain. But who foresaw that the man who was declared unfit to be minister of defence would bounce back as prime minister?

During the 2001 elections campaign Sharon tried to reinvent himself as a man of peace. His spin doctors cultivated the notion that old age was accompanied by a personal transformation from a sanguinary soldier into a genuine peace-seeker. President George W Bush famously described Sharon as "a man of peace". For the last 40 years the Arab-Israeli conflict has been my main research interest, and I have not come across a scintilla of evidence to support this view. Sharon was a man of war through and through, an Arab-hater, and a pugnacious proponent of the doctrine of permanent conflict. Following his rise to power Sharon therefore remained what he had always been – the champion of violent solutions.

The dominant preoccupation of Sharon's premiership was the "war on terror" against militant Palestinian groups. No peace negotiations with the Palestinian Authority took place between 2001 and 2006, and Sharon regarded this as something to be proud of. To his way of thinking negotiations necessarily involve compromise, and he consequently avoided them like the plague.

For this reason he also rejected all international plans aimed at a two-state solution. One was the 2002 Arab peace initiative, which offered Israel peace and normalisation with all 22 members of the Arab League in return for agreeing to an independent Palestinian state on the West Bank and Gaza, with a capital city in East Jerusalem. Another was the 2003 Quartet road map, which envisaged the emergence of a Palestinian state alongside Israel by the end of 2005.

Sharon was the unilateralist par excellence. His ultimate aim was to redraw unilaterally Israel's borders, incorporating large swaths of occupied territory. Stage one was to build on the West Bank the so-called security barrier which the Palestinians call the apartheid wall. The international court of justice condemned this wall as illegal. It is three times as long as the pre-1967 border, and its primary purpose is not security but land-grabbing. Good fences may make good neighbours, but not when they are erected in the neighbour's garden.

Stage two consisted of the unilateral disengagement of Gaza in August 2005. This involved the uprooting of 8,000 Jews and the dismantling of many settlements − a shocking turnaround by a man who used to be called the godfather of the settlers. Withdrawal from Gaza was presented as a contribution to the Quartet's road map but it was nothing of the sort. The road map called for negotiations; Sharon refused to negotiate. His unilateral move was designed to freeze the political process, thereby preventing the establishment of a Palestinian state and maintaining the geopolitical status quo in the West Bank.

The legal term "depraved indifference" refers to conduct that is so wanton, so callous, so reckless, so deficient in a moral sense of concern, so lacking in regard for the lives of others, and so blameworthy as to warrant criminal liability. Sharon personified this kind of indifference in his approach to the Palestinians.

Towards the very end of his active life he bolted from the Likud to create the centrist party Kadima, but Kadima did not survive his demise. Today it has only two seats in the 120-member Knesset. So Sharon's last-minute attempt to bring about a realignment in Israeli politics ended in failure.

His enduring legacy has been to empower and embolden some of the most racist, xenophobic, expansionist, and intransigent elements in Israel's dysfunctional political system.

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