Washington to U.N. peacekeepers: don't call us, we'll call you. After Sierra Leone, no one wants to send the United Nations into a war zone alone any time soon. The debacle of the last few weeks was a horrifying capstone to a series of post-cold-war U.N. peacekeeping disasters dating back to Bosnia in 1993. None of these, of course, was entirely the United Nations' fault. The world body has few resources and no mandate to form its own combat force for taking on the Foday Sankohs of the world. It's unlikely to get one, either. U.N. Security Council members, especially the United States, don't want to beef up the United Nations because they fear it might infringe on their sovereignty (remember the "black helicopters"?). Nor do they want to risk their own soldiers' lives in U.N. efforts far from home. Congress's recent moves to cut even more from an already slender foreign budget only punctuates that harsh reality.

Instead, what has been emerging in recent crises—Kosovo, East Timor and now Sierra Leone—is a new pattern of regional intervention. It is a hard-nosed alternative to the old model of blue-helmeted multinational peacekeepers armed mainly with the moral prestige of the United Nations. Senior U.S. officials concede that, while U.N. resolutions are still necessary to legitimize intervention, Washington may not have much choice but to borrow the military muscle of a big regional power like Nigeria. That was true in East Timor last fall, when Bill Clinton happily accepted Australia's offer to send in combat troops to stop Indonesia's murderous militias. It was true in Kosovo, too, where the United States decided to leave peacekeeping mainly to NATO after U.N. forces failed to stop atrocities earlier in Bosnia.

Now the pattern is spreading to Africa. "Sierra Leone has only re-emphasized this" need for a regional power to step in, says U.N. Ambassador Richard Holbrooke. What U.S. officials realize is that Foday Sankoh's brutal rebels, who broke the peace, took their cue from the departure of the Nigerians—the only troops truly stronger than they were. Now Clinton is asking the Nigerians back in and plying them with aid and support, including a U.S. Navy sealift around the coast of Africa. "Only national forces are basically competent," says a Pentagon planner. Secretary of State Madeleine Albright fortunately laid the groundwork last year with a visit to the newly democratized Nigeria.

The consequences of relying on regional enforcers around the world—rego-cops?—could be far-reaching. Washington will have to act less unilaterally and become more indulgent of others' agendas. And a scaled-down United Nations will undoubtedly bring scaled-down expectations for U.N. peace pacts. But today, as new conflicts rage worldwide, policymakers will do whatever it takes to stop the killing.