The fierce fight at the Euphrates river-crossing at Nasiriyah, and the vigorous harassment of British forces on the outskirts of Basra, not only thwarted US and British plans for a bloodless victory over the Iraqi regime. The resistance from soldiers and civilians in southern Iraq breathed life into what had seemed until that point the deadest dog in international politics: the political ideology known as Arab nationalism.
With its tired paraphernalia of cement socialism, personality cults, hyper-literary rhetoric, police repression and military adventure, Arab nationalism had been written off as mori- bund ever since the crushing defeat of the Arab armies by Israel in 1967.
Saddam Hussein's invasion of Kuwait in the summer of 1990, which punctured the facade even of a rhetorical Arab unity, appeared to have delivered the coup de grace. Instead, the pan-Islamic ideology promoted by Osama Bin Laden and the veterans of the 1980s Afghan revolt against the Soviets excited the imaginations of a dejected and demoralised Arab world. Yet the events of the past week have shown that news of the death of Arab nationalism may be premature.
Imagine that Saddam Hussein - or some member of his family or inner circle - survived the US onslaught with control of a portion of Iraq. The result would be a profound alteration in the distribution of power in the Arab world.
The western allies in the region would be obliged to accommodate an Iraq as self-confident as when Saddam attempted to displace Egypt as the head of the Arab world in 1978. In Iran, the anti-reform and anti-American forces would be strengthened, while the Palestinian radicals in Gaza and the West Bank would feel they could reject any accommodation with Israel. The would-be suicide bombers and Binladenites, orphaned by the destruction of their Afghan base two winters ago, would come under the protection and sponsorship of one or other Arab state.
As for Saddam, he would be crowned with the aura of Gamal Abdel Nasser after he frustrated the Anglo-French-Israeli attempt to seize the Suez Canal in 1956. Saddam, not Bin Laden, would be on Arab children's T-shirts.
That is not a likely outcome. But in a region as desperate for champions as the Arab world, even a week's resistance against the force and technical ability of the United States will be hailed as the work of a hero. Those Arabs who secretly rejoiced at the attacks on New York and Washington on 11 September 2001 openly praise the defence of Iraqi cities. Remember, Saddam and his allies treated as victory even the ignominious retreat from Kuwait in January 1991 and commissioned interminable panegyrics in medieval Arabic on the theme of the "mother of all battles".
In those circumstances, Britain and the US may come to regret not leaving this particular animal alone.
Arab nationalism, which began life in secret societies in the Arab contingents of the Ottoman army before the First World War, has always defined itself as a struggle against non-Arabs: first the Ottoman Turks who administered much of the eastern Arab world until 1918, then the British and French mandatory powers, then Jewish immigrants in Palestine and finally the state of Israel.
Iraq itself was established by the British in the closing years of the First World War. Having been shown the perils of long supply lines from Basra when an army from British India was forced to surrender to the Turks at Kut on the Tigris in 1916, the British captured Baghdad the following year and then brazenly detached a third Ottoman province, that of Mosul and including the Kurdish mountains, at the armistice in 1918.
Welcomed at first as guarantors of security and Arab independence, the British then made themselves thoroughly unpopular by insisting first on their mandate over Iraq and then a bullying treaty of friendship. The British officials, led by the high commissioner, Sir Percy Cox, and his oriental secretary, Gertrude Bell, overestimated the prestige of the British empire and their own popularity.
In a premonition of the confident postures of modern British and American officials, Bell wrote in June 1920: "There is no doubt they are turning to us." A couple of weeks later began the first of several armed uprisings against the British among the Shia tribes of the Middle Euphrates.
The monarchy established by the British was always regarded as a puppet, and once British influence in the Middle East was broken at Suez in 1956, its days were numbered. Drawing from the example of Arab nationalist officers in Egypt, a republican insurrection destroyed the Iraqi monarchy and the British alliance in 1958.
Saddam's Arab Ba'ath Socialist Party had been founded as a study group in the Damascus of 1940 by a Sorbonne-educated Greek Orthodox intellectual named Michel Aflaq and a Sunni Muslim, Salah al-Din al-Bitar. It sought to unite the variety of creeds and communities in the eastern Mediterranean into a predominantly secular political force. Its Iraqi counterpart was established by Syrian exiles in the early 1950s, and seized power in the chaos that followed the Arab military defeat of 1967.
In the period from the middle 1970s, strong markets for Iraqi crude oil allowed the Ba'ath to spread a veneer of prosperity over the deep religious and tribal divisions in Iraqi society. Before the latest war, Sunni families in Baghdad and even Arab intellectuals from outside Iraq would speak nostalgically about the technical civilisation that the Iraqi Ba'ath was in the process of creating.
In reality, a cult of brutality and naked power had long replaced both the socialist and the pan-Arab ideologies. After Anwar el-Sadat made peace with Israel at Camp David in 1978, Saddam sought to exploit Egypt's isolation and take over the leadership of the Arab world. The long war with Iran ruined the prosperity on which the Ba'athist regime based its appeal. After the first Gulf war in 1991, Saddam quelled an uprising in the Shia south but lost control of Kurdistan, which became a sort of undeclared UN protectorate. In the new religious atmosphere, he began constructing mosques, and put it about that Aflaq had converted to Islam before his death in 1989. Saddam himself discovered that he was descended in a direct line from the Prophet's family, which is revered by the Shia majority in Iraq.
These ploys may have been more successful than was imagined. More to the point, the first week's fighting in Iraq reminded the world of two truths. Most Iraqi Arabs hate the Ba'ath and Saddam Hussein for the misfortunes they have brought on a fertile and rich country. But they do not like or trust the British and Americans.
They will wait to see who is successful.
James Buchan has reported from the Middle East since the 1970s