Historically, this is a difficult transition to achieve. Even if the political will exists to contribute to a peace-keeping force, the details of assembling it and deploying it will be ferocious.
This is work that will begin in earnest at UN headquarters this morning. Participating in some of it will be Ali Alatas, the Foreign Minister of Indonesia, who was dispatched by President B J Habibie to New York last night. The Security Council must also pass a resolution laying out the force's mandate.
In theory, an all-Australian force could enter East Timor today. But Indonesia has not agreed to an Australian invasion. The force will be a multinational one, almost certainly dominated by troops from Indonesia's Asian neighbours. President Bill Clinton's national security adviser, Sandy Berger, said the United States hopes the peace-keepers will deploy "in the next several days. This will involve US troops," Mr Berger said. "Some of those troops will be in Timor but they will be, I think, of limited numbers. And I don't want to rule out anything categorically but the focus is not on infantry forces."
The United States will supply planes and pilots to carry troops, and help with logistics, communications and intelligence, Mr Clinton said.
Mr Berger said there would be no further need for sanctions if the peace- keepers were allowed to deploy promptly without restrictions.
He said the peace-keepers must be allowed to help restore order and oversee the implementation of the independence referendum. But he said: "The responsibility still rests squarely on the Indonesia military to restore order to the situation."
Britain, stretched in the Balkans, is unlikely to supply more than logistical support.
Even under the best of scenarios assembling and deploying the force is likely to take three weeks, a senior UN official suggested last night. Officials will be negotiating with Mr Alatas what happens next to the Indonesian forces who are now in East Timor implementing martial law. A timetable needs to be established for the phased winding down of those troops as the peace-keeping force begins to deploy.
Some of this was discussed by the five-member Security Council mission with President Habibie and his chief commander of the army, General Wiranto, in Jakarta last night. Expelling all of the Indonesian soldiers to make way for the UN deployment is not likely to happen. The UN appears ready to accept that some Indonesian soldiers remain to work with the incoming force.
Excluding the national army would deepen Jakarta's humiliation. But the UN appears anxious that Indonesia should not escape all of the responsibility for making the peace-keeping mission work. If Indonesian troops remain, however, it is likely that they would be used only in parts removed from the worst of the mayhem.