"If the Taleban come, we will stop them," said Alem.
The eyrie he guards is at the heart of the legendary Hindu Kush, a barren mountain ridge that stretches across the breadth of Afghanistan in a jagged granite wall dividing north from south.
Perched at the very crest, in a nest beside a heavy machinegun, Alem has spent the past 21 of his 60 years battling in the Salang Pass.
With his nephews, he commands a machinegun, six Kalashnikovs, two grenade launchers and a spectacular view of a green lake and the mountain road descending to the north, from where any Taleban advance would probably come.
The American military, who may be hoping to dislodge the Taleban with a mixture of airstrikes and special forces operations far to the south, will be counting on Alem and his nephews to hold firm.
For Alem's Northern Alliance, which has battled the Taleban since the puritanical Islamic movement threw them out of power five years ago, the key to victory lies in cutting off the Taleban troops in the north from their southern bases by sealing the routes across the Hindu Kush.
The main route is this pass, where the Soviets once built the world's highest tunnel, linking Central Asia to the Indian subcontinent. Its strategic importance is legendary. Soviet troops battling to keep the route open called it the Road of Death. They never held it securely, and the carcasses of their tanks still litter the gorge.
Today, it is in the hands of the alliance, which has dynamited the tunnel's entrance and guards the pass above it.
Without this route, Taleban forces in the north must use alternative supply routes that take days instead of hours, said General Basir Salangi, who commands the alliance forces here. "That is why getting this gorge is their greatest dream," he said.
The alliance is hoping not only to keep Salang shut but to close the alternative routes as well, allowing their forces in the north to deliver a quick and decisive blow to Taleban fighters trapped there.
Alliance officials say they hope American strikes will make that possible, both by providing support for an alliance assault and by persuading local commanders allied to the Taleban to switch sides.
"If we can close those roads and America strikes the Taleban, we can take Mazar and Kunduz," said Salangi.
"Within a week we can sweep the Taleban out of the north. They will be left with nothing but their bases near the Pakistani border. You can write that down. You'll see."
Up on the mountaintop, Alem knows little of any US plans. Soviet air strikes killed his father, his brother and his sister. Now, he sees the Pakistan-backed Taleban as the invaders.
His 18-year-old nephew Abdul Said has been armed and at his side for four years.
Alem's few remaining teeth are yellow, his white beard is thinning, but he darts nimbly up the cliffside carrying a box of ammunition.
"As long as I still have the strength, I will go on fighting," he says.
- REUTERS
Map: Opposing forces in the war against terror
Afghanistan facts and links
Full coverage: Terror in America