It might be said for occupying military forces over the centuries that the singular characteristics of Afghanistan - the rugged terrain, the tribal make-up, the fierce independence of its people - have placed it somewhere between a rock and a hard place.
That modern invaders insist on finding this out for themselves speaks on the one hand of a cavalier disregard for the lessons of history and, on the other, of a complex set of contemporary geopolitical forces which all too easily entwine this vast and unyielding country's antagonists.
So it proved for the Soviet Union, which waged an occupation war for almost 10 years from late 1979, finally departing in abject failure in February, 1989.
And so it may yet prove for 2009 Nobel Peace laureate President Barack Obama of the United States.
Last week, he announced his long-awaited strategy for Afghanistan, which comprised the commitment of 30,000 additional US troops to the Nato counterinsurgency, but which also named July, 2011, as the date on which those troops would begin to desist and depart.
Mr Obama and his close advisers are too smart not to have anticipated reaction to the plan, but even they may have been surprised with the vehemence with which it has been greeted - by political friends and foes alike.
As long ago as the early days of the presidential election campaign, Mr Obama indicated that he would rapidly seek to withdraw US troops from Iraq but bolster forces in Afghanistan.
That policy has taken many months to take shape, but now that it has, the President seems determined to make haste.
On Wednesday last, he told the American people that he had ordered tens of thousands of US reinforcements to Afghanistan to take on the Taliban, secure the country and hand it back to its own security forces - all within three years.
He has pledged 30,000 reinforcements and has prevailed upon Nato allies, through the offices of Secretary of State Hillary Clinton, sent last week to Brussels, to provide at least 5000 more troops, as well.
At a stroke he alienated the liberal wing of his own party, which believes the war is unwinnable and that American troops should not be there in the first place; and many Republicans for whom coupling the announcement of reinforcements with a withdrawal date was tantamount to ceding critical psychological and practical advantage to the Taliban.
What is to stop them simply hunkering down and waiting the Nato forces out? It, will of course, be of little comfort to the US administration that both points of view have some merit.
To the extent that the troop escalation represents a victory for the US ground commander General Stanley McChrystal, it is also an endorsement of the general's counterinsurgency plan: to secure and control the country's 10 largest centres and from this position of strength to win the trust and support of ordinary Afghanis.
At a more removed, strategic level, the hope is to recruit and train sufficient Afghan troops and police to be able to take over security operations themselves within three years.
Critics are already saying this is a forlorn hope.
Presidents and prime ministers are either made or broken on the back of military conflicts.
That much it seems has not changed, between Alexander the Great and Leonid Brezhnev's Soviet Army.
Like the proverbial Waterloo of Napoleon, like the Vietnam of LBJ and Richard Nixon, names such as Helmand province and the Taliban stronghold city of Kandahar, along with the casualties incurred in their "liberation", are likely to be seared on to the American psyche for years to come.
This is not an association a president would lightly choose for himself, and given the potential political cost, it can only be imagined that Mr Obama, and his closest advisers, felt they had little choice in the matter.
But with salvos coming in from all sides, there may be much muttering in their tightly encircled camp about rocks and hard places.
