Looking down on Kosovo from this vantage point high on Koshare Mountain on the Albanian frontier, it is easy to see the problem confronting NATO's military planners. Or rather, it isn't.
Somewhere, hidden in that maze of towns, villages, hills, gullies and thick forest are the hundreds of tanks and thousands of men deployed by the Serbs. But you cannot see any of them. Nor, unless it can spot tanks through thick foliage, can NATO. The alliances's air bombardment can go on and on but short of bombing every house and tree on the Jakovo plain there is no way of guessing under which trees the Serbs have hidden their tanks.
And as Tony Blair, due to visit Albania today, is no doubt well aware, NATO is in fact in danger of bombing its way into a stalemate.
Up here, the rebel Kosovo Liberation Army is busily reinforcing, with hundreds of soldiers, an enclave they have pushed five miles inside Serb territory. KLA soldiers point to distant hills, where smudges of brown mark the places where Serb guns were foolish enough to open fire on the KLA, and were subsequently destroyed by NATO bombers.
The Serbian artillery down there is now silent, and barring a single Serb shell, all the noise yesterday is made by the sporadic firing from the mortars of the KLA. The KLA wants to push south, capturing the road that would allow them to bring supplies through a mountain pass from the Albanian town of Bajram Curri to Jakovo. But on its own, the KLA lacks the armour and heavy guns to break out from their enclave into the clear country beyond.
The only way to get the Serbs out of Kosovo through direct action is to invade with ground troops, or for NATO to establish a more direct relationship with the KLA, supplying the sort of weapons and close air support that is likely to enrage Serbia's ally, Russia. Analysts say the alternative - bombing Serbia until it changes its mind - will only work if the alliance is willing to bring about the complete collapse of this country, including its water, power, food distribution and sewerage systems.
Even then, NATO could find that the Yugoslav President, Mr Slobodan Milosevic, will probably hang on, even as Western TV channels fill with pictures of hungry Serb children dying in blacked-out hospitals, or hundreds of tons of raw sewerage float down the Danube.
Mr Blair, of course, hardly needs convincing. Britain, alone among Allied powers, has said it is willing to use ground troops if these air strikes fail to persuade the Serbs to cave in of their own accord. Mr Blair's main crime, in the eyes of Britain's military establishment, is the lack of foresight as to what would happen if, as is now the case, those Serbian guns and tanks remain tantalisingly out of view from NATO's jets on the Plain of Jakovo.
Only now is the alliance scrambling to find a way out. Sharing space on the decrepit ferry boat that took us through a spectacular Albanian loch to the town of Bajram Curri, were the first contingent of American troops.
These soldiers, sitting among their HUMVEE armoured Jeeps, each jammed with communications equipment, were evasive about their mission up here in Albania's wild north-west. But they appeared to be the advance guard, together with some Albanian special forces, of a military base being set up in the hills to better co-ordinate the expected escalation of NATO's campaign. Apache attack helicopters are the star element in this escalation, but at present they are little more than a distraction.
Like NATO's bombers, the Apaches cannot hit what they cannot see, and are unlikely to cruise around Koshare Mountain searching for stray tanks amid the risk that the Serbs will fire a shoulder-launched anti-aircraft missile at them. More likely the Anglo-American artillery and surface-to-surface missiles now arriving in Albania will be put to use.
But like the bombers, such weapons, short of turning large swathes of Kosovo into scorched earth, are of little use unless they are supporting the seizure of territory by a ground force. Up here - I am not allowed to reveal exactly where - KLA soldiers sat in a stone farmhouse surrounded by boxes of everything from ammunition and medicine to computers and white military police belts contemplating their fate.
"We have plenty of men, more and more keep coming, but we need some big weapons," said one. "When will NATO end its embargo?" The question is not easy. NATO can begin supplying heavy weapons to the KLA, and see Russia do the same with the Serbs, starting an arms race. Or NATO can bomb Serbia until it starves, or send in ground troops or throw in the towel, halt the air strikes, and set about finding homes for one million embittered Kosovans.
What the alliance cannot do, however, with the Serbs now well hidden, is to cross its fingers and carry on bombing. Anyone on Koshare Mountain can tell you that.
AFP adds:
The moderate Kosovan leader, Mr Ibrahim Rugova, yesterday said, "Kosovo is empty," after a meeting in Brussels with the Belgian Foreign Minister, Mr Erik Derycke. He estimated only some 200,000 ethnic Albanians remained.
"I left (Kosovo) to work and create possibilities for people to return because Kosovo is unfortunately empty today," Mr Rugova told a press conference.
"The best thing (for Kosovo) would be independence, to bring calm to the region. But before that, I hope Kosovo will be repopulated, because I lived in an empty Pristina, terrified by that ghost town," he said.
Mr Rugova had told the Belgian minister some 200,000 ethnic Albanians may remain in the southern Yugoslav province, a spokesman for Mr Derycke said.
International organisations say a total of 580,000 Kosovans are believed displaced within the province and living outdoors.
In response to a question on Kosovo's future, the moderate leader called again for its independence.
"We have a right to independence, because we were part of a country which no longer exists, the former Yugoslavia," Mr Rugova said.