Yesterday’s assassination attempt on the President of East Timor is the second reminder within a year that the six-year-old country, so often pronounced a triumph for United Nations intervention, is also a whisker away from failure.

Like Kosovo, which is within days of declaring its independence, East Timor is a lesson in how long it takes to build a new nation. But the need for years, or decades, of painstaking development work – and money – conflicts with the inevitable impatience from the international community, and with the limited tolerance of the country itself for the presence of foreign advisers or troops.

However, the most precise lesson from East Timor, reinforced by Kosovo, Afghanistan, Iraq and Northern Ireland, is the difficulty of setting up an army and a police force trusted by all the population.

Government officials yesterday blamed Alfredo Reinado, leader of a group of former military officers, for the attack by gunmen on President José Ramos-Horta, and on a convoy carrying Xanana Gusmão, the Prime Minister. A spokesman said Reinado was killed in the shoot-out. If true, then the roots of the attack go back to last year’s crisis between the police and the army – and to questions about the army’s role, which the UN ducked for nine years.

East Timor won independence from Indonesia in a referendum in 1999, and after three years of UN administration, it became a sovereign nation. International Crisis Group (ICG), the Brussels-based research group whose board includes many former foreign ministers, in a prescient report three weeks ago, gave warning that the problems in East Timor’s security forces threatened its governability. “In the country’s short history, its politicised, undisciplined and poorly structured security forces have amply demonstrated their capacity to create or aggravate social conflict,” it said. Attacks by police on soldiers and vice versa since independence – one prompted by a volleyball match – led to a crisis in 2006, in which half the army was dismissed.

At independence, when some soldiers were demobilised, the payoff “failed to satisfy their expectations or economic needs”, said ICG – a problem with echoes in Iraq. Some of the disaffected former soldiers are thought to have been behind yesterday’s attack.

The numbers involved are tiny, it should be said. The army had 1,435 soldiers in January 2006 and 715 after that crisis; the police force has numbered about 3,200, for a population of a million. But that has not brought intimacy; the forces are plagued by cultural divisions between the east and west.

The UN was guilty of “avoidance and wishful thinking” about the army, and the division of its responsibilities with the police, the ICG report added. The Government has also been too ready to call in the army, rather than the police, to handle unrest. But ICG asks gently whether, despite East Timor’s long history of invasion, by Portuguese, Japanese and Indonesians, it now needs an army at all. It has more need for a navy, to tackle illegal fishing and drugs, although its current navy is only 36 people.

There is nothing about the latest violence in East Timor to suggest that international intervention does not work. In contrast, it shows that intervention can succeed in putting a lid on the violence. But it does not, on its own, help to build institutions which are absent. The US Army’s new operations manual, released formally later this month, will give those tasks equal weight with victory on the battlefield, in a marked shift of focus which shows that Iraq and Afghanistan have driven that lesson home.

The common experience of Kosovo, Iraq, Afghanistan and East Timor itself is that after the judicial system, policing is the hardest institution to set up. It takes years, at the least. Yesterday was a reminder that sovereignty is the beginning of that long process, not the end.

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