BY flexing its airpower muscle in the Balkans, the United States and its NATO allies have attempted the difficult task of trying to look tough enough to deter Bosnian Serb aggression without provoking retaliation against United Nations peacekeepers, or UN-protected Bosnian Muslim enclaves.
Western credibility on Bosnia had appeared to dwindle last week, as Serb forces continued to pound the town of Gorazde, and some US officials openly said force would not be used to prevent the enclave's fall.
F-16 and FA-18 airstrikes against Bosnian Serb forces Sunday and Monday were NATO's way of saying, ``We still mean it. Stop fighting and negotiate a settlement.''
``The whole point here is to send a message,'' says Daniel Nelson, an international affairs expert at Old Dominion University in Norfolk, Va., and a frequent visitor to the former Yugoslavia.
As Mr. Nelson notes, previous credible NATO sword-rattling produced results in Bosnian diplomacy after months of fruitless talking. Threats of airstrikes lifted the shelling siege of Sarajevo. Life there is not yet normal but is far safer than before.
But sending political messages via the use of military force is not without risks. Nations with troops serving on the ground in Bosnia as UN peacekeeping forces have long worried that Serbs might at some point overreact and launch concerted attacks on blue-hat peacekeeping forces, inevitably drawing NATO into further fighting. Last year, the UN had declared six areas as safe enclaves for Bosnia Muslims.
NATO now appears to have erected a tripwire around Gorazde. Having carried out airstrikes to protect the handful of UN forces in this Bosnian town of 65,000 some 35 miles southeast of Sarajevo, what would the West do if Serb forces continue to press their attack to take the town? An all-out air attack would surely have the effect of drawing NATO further into the war on the side of the Bosnian Muslims.
President Clinton on Sunday made it clear that further attacks would be contemplated if Bosnian Serb forces continued to try to take Gorazde or other UN-declared safe havens. But at the same time he insisted that what had happened so far was simply a limited act of peacekeeper defense.
``All we're trying to do is further negotiations,'' said Mr. Clinton.
As of this writing it was not clear whether NATO airstrikes had in fact halted Bosnian Serb attacks on the Gorazde area.
Bosnian government radio indicated that infantry fighting continued, and US-led air forces delivered another round of bombs yesterday.
Airstrikes alone might well be unable to prevent Serbs from taking Gorazde. Massed targets are few, unlike in the Sarajevo area, where dug-in heavy artillery were somewhat vulnerable to air attack. Serbs have already pressed so close in to the center of Gorazde that some of their forces are close to civilians, raising the threat of civilian casualties.
The Bosnian Serb leadership declared that it would not be intimidated by NATO warplanes and that it was breaking off contacts with UN peacekeepers, and suspending planned talks with US special envoy Charles Redman.
Bosnian Serb politicians may not have complete control over their military, in any case. Bosnian Serb military commander Gen. Ratko Mladic is more radical than political leader Radovan Karadzic and opposes negotiations to end the war - and General Mladic's strong support among his troops gives him a power base that Mr. Karadzic himself cannot match.
Russia may also become a more complicating presence in the Balkans now that NATO has struck Serb targets on the ground. Russia is a traditional ally of the Christian Orthodox Serbs and has played the role of Serb protector in recent negotiations.
Russian President Boris Yeltsin strongly protested NATO bombing raids over the weekend. Mr. Yeltsin told reporters that he had phoned President Clinton and insisted that Russia be consulted before any further NATO military action.
Ironically, the airstrikes Sunday and Monday were the first time that NATO munitions have exploded on the ground in the alliance's 45-year history.
An earlier air-to-air wrangle that resulted in the downing of Serb warplanes had been the first time any shots had been fired in NATO's name. That air attack helped result in the city of Sarajevo regaining some peace for now.