FOR more than a decade, the war in El Salvador ground on, eventually killing at least 70,000 people and leaving a trail of human rights atrocities.
But as of last weekend, as a United Nations observer mission packed up after four years of work, the country's grim past no longer shrouds its future.
Not that large problems don't remain. Plans for land redistribution, a key element in the peace agreement worked out in 1992, are far from full implementation. Opponents of such efforts to give an economic stake to the poor -- including both former rebels and soldiers -- are still active. But the signs of transformation are many.
The country's military, which ballooned to 56,000 troops at the height of the conflict, has shrunk. Units and officers known for brutality are gone.
A Truth Commission chronicled the violence against civilians during the war -- an exercise in self-examination crucial to establishing a climate of justice. The judicial branch of government, once corrupt and ineffectual, has been rebuilt.
A National Civilian Police body has replaced the old, widely feared security forces. It includes recruits from both sides in the war. While the police service is establishing better relations with the public, its progress has been slowed by inadequate resources and by attempts to include people with checkered histories.
Another element in the UN-brokered peace plan is incorporation of the rebels -- the Farabundo Marti National Liberation Front -- into the Salvadoran political process. The FMLN is now the largest opposition party in the national legislature, operating in relative harmony with the ruling Arena Party, which in the past was closely associated with rightist militancy.
El Salvador offers many lessons, but none clearer than the effectiveness of peacekeeping in an environment -- vicious though it may have been -- where warring sides recognize the futility of continued combat.
The benefits of peace haven't all filtered down yet to the average Salvadorans who suffered most from the war.
But in the long term their lives should be incomparably better because of an international intervention that worked.