In the first stages of the multinational force's deployment in East Timor, it was vital to get troops in as fast as possible, not only because small numbers are vulnerable, but also to give an impression of resolve and strength, so gaining a psychological advantage over potential opposition.

The signs are that the Australian-dominated force has achieved this, with a fast and efficient entry. For the Australians, this whole mission is a huge challenge for armed forces that have seen little action since the Vietnam War in the 1960s.

However their relatively small armed forces are tough, capable and highly professional.

What the force will be watching for now is the attitude of the Indonesian army, the TNI. They outnumber the international force, and they must remain at least neutral if the mission is to succeed.

An Australian soldier stands guard near the port in Dili

The early signs have been good, and commanders have expressed confidence that Indonesian commanders, having accepted the international force as a fact of life, will keep their troops out of the way.

One uncertain feature though is what control the Indonesian high command have over local military forces.

It is generally believed that many units have been pretty well out of control, and they will certainly resent the presence of foreign troops.

The reaction of the militias, responsible for most of the recent brutality, is also unclear. Although the Indonesian government denies it, there is no doubt the militias were operating semi-officially.

However the militias are both vicious and ill-disciplined, so even if the Indonesian military tell them to back off - it is not certain that they will.

Acting tough

Well-armed troops are a very different proposition to unarmed civilians, and the international force has a UN mandate to use "all necessary means" to carry out their mission.

In these circumstances it is vital that in any early encounter the international force acts tough.

Experience in places like Bosnia and Kosovo shows that if it does word will soon spread, saving later trouble, but the reverse could also happen.

Certainly the Australians have been taking a no-nonsense approach, as has the British contingent of Gurkhas.

It is less clear how some other national contingents will react, especially some Asian nations.

Their troops are competent, but their governments are extremely cautious about provoking their Indonesian neighbours, and if things go wrong it could reveal splits within the hastily organised international force.

The sheer number of nations, with small contingents, could also be another problem. An efficient military operation requires good teamwork from countries who know each other, but this force is a bit of a hotch-potch.

Potentially vulnerable

As the force spreads out into the countryside, fanning out into smaller groups, they are potentially vulnerable to attacks from militia bands, who may not take on proper units, but will be on the lookout for isolated groups or individuals.

The dangers were demonstrated by the killing of a Dutch journalist by suspected militia members, and a shooting incident involving militia members in Dili, which prompted peacekeepers to fire their first shots.

The troops must also secure the main routes so aid can move in fast, protect the large numbers of Timorese thought to be in the hills, and ultimately get them home.