If peace is a real possibility in Kosovo, and the talks currently being hosted by France and Britain in Rambouillet really are near to a solution, then the allies are right to extend their earlier deadline.
But it is increasingly hard to believe that this is the case.
Nato's overwhelming military muscle and its ability to attack any Serbian targets it chooses is beyond doubt; what these attacks would really achieve is far less certain.
The West's weak position has once again been shown. It is a similar weakness to that so clearly revealed following the recent US and British air strikes on Iraq. While these attacks inflicted damage and perhaps delayed Saddam Hussein's weapons programmes, they did not alter the political landscape one jot.
It is now quite clear that Serbia's leader, Slobodan Milosevic, has been able to remain intransigent over the question of the deployment of Nato peacekeeping troops despite threatened air strikes, while creating the impression that there is still the possibility of a peace deal.
By refusing to budge before the air strike deadline, he has called the West's bluff and, to an extent, has won: the deadline has been extended.
The West is right to take a threatening stance and it is right to dictate a timetable after which decisive action will be taken. But once these deadlines are reached then the threatened action must be taken. Extending deadlines merely indicates a reluctance to act decisively.
Even so, punitive air strikes would be just the beginning. It is unlikely that by themselves they would bring a more compliant Serbia back to the negotiating table.
The violence in Kosovo is part of a civil war - it is still legally part of Yugoslavia, despite the desire for independence from the overwhelming majority Kosovo Albanian population. Involvement in a civil war is a far more complex and potentially messier prospect for the West; mishandled, and Balkan stability could be even further undermined.
US President Bill Clinton makes threatening noises but is offering only a tiny proportion of the 30,000 troops it is expected will be required to make up the peace force, leaving Britain and France to provide the real military weight on the ground. Russia has made it plain that it is strongly against the use of force.
Serbia recognises these weaknesses. And now there is a further blow - the prospect that even if Serbia can be persuaded to agree to a peace deal, the Kosovo Albanians may not. In which case, air strikes against Serbia would be futile.