BY threatening airstrikes if Bosnian Serbs do not move heavy artillery back from the hills surrounding Sarajevo, NATO has taken a large step down the risky road of military involvement in the Balkans war.
NATO bombs, or the threat of NATO bombs, could well remove the big guns that have shelled Sarajevans for months. But air power by itself won't stop the bitter fighting, or even end the possibility of tragedies similar to last weekend's mortar attack on a Sarajevo market.
If increased United States pressure does not lead to a political settlement between Bosnian Serbs and the Muslim-dominated Bosnian government, NATO's next military step is unclear. Imposing peace would take more troops and planes than Western nations have said they are ready to commit. ``This is not a situation that can be fixed with force,'' notes John Macartney, an American University professor and former Air Force pilot.
As of this writing the new NATO threat appeared to be having some effect. Bosnian Serbs reportedly had agreed to remove their artillery from approximately 22 firing positions ringing Sarajevo.
Yesterday, however, Bosnian Serb leader Radovan Karadzic walked out of Geneva peace talks. Mr. Karadzic said he would not return unless Muslims agreed to a joint commission to investigate last weekend's mortar attack. Most Western observers suspect a Serbian soldier launched the deadly round, but Karadzic has heatedly denied the charge.
The estimated 500 large pieces of artillery are only a part of Sarajevo's problem. Snipers and easily transportable mortar units have also taken a heavy toll in the city's two-year-long siege.
The round that killed 68 last Saturday is thought to have come from a 120mm mortar, for instance - a weapon that can be swiftly moved by three men and a truck. Late last month, six Sarajevo children were killed by a shell from a 60mm mortar, which can be easily carried by a single soldier.
Short of going house-to-house in the hills with ground troops, NATO cannot eliminate the Serbian ability to shell Sarajevo. Thus the demand to pull back heavy weapons ``has far more symbolic value than practical value,'' judges Dan Nelson, an Old Dominion University professor who visited the city last month.
If the Bosnian Serbs do not wheel back their artillery within the 10-day period, NATO warplanes could suppress many of them. The guns are dug in and camouflaged, and some are located in civilian areas. But allied planes have had months of practice-bombing runs in the target area, and they have honed their communications tactics with forward air-control spotters on the ground. NATO spotters now need only two or three minutes to guide pilots onto targets, according to reports from the region. Spotters can also employ hand-held laser designators that guide precision-guided munitions as they plummet to the ground.
A more effective means of counterartillery fighting would be to base US shell-tracking radar in Sarajevo, coupled with large NATO guns. With such equipment, US troops could return fire before incoming rounds land. But US officials have rejected ground deployments as too dangerous.
Currently the allied air force in the region, based at Aviano Air Base in Italy, is relatively modest, consisisting of US F-16s and A-10s and F/A-18s, as well as French Mirages and other allied craft. Chairman of the Joint Chiefs Gen. John Shalikashvili said this week that NATO power could certainly achieve the limited purpose of halting the firing of Serb heavy weapons. Beyond that, he admitted, its efficacy is less clear. ``Air power alone cannot bomb someone into a peace treaty,'' he told Congress.
Once the first bomb falls, however, the US and its allies will inevitably be seen as having taken sides in the conflict.