Sailor: in some limited respects, I agree with you. If you are defining a stable nation as one with a strong central government, then Afghanistan has only intermittently qualified. It is, after all, a conquest state in origin, multi-ethnic and tribal, with a strong tradition of factionalism. Much like Burma/Myanmar, which was formed around the same time under roughly similar circumstances, or like any medieval state you care to mention, the degree of authority wielded over the periphery of the country fluctuated with the ability of the ruling sovereign. In Afghanistan, the Pashtun tribes taken as a whole have always wielded enormous political influence and have, more often then not, had a fair degree of internal autonomy.
That said, I think I am going to agree with tomndeb and Yue Han and say that you are overstating the case a bit. In the decades before the Soviet invasion ( even after the coup that removed Zahir Khan ), the state was showing real, if slow and intermittent, progress. Yes it was still desperately poor and undeveloped, with banditry and bloodfeuds in the backcountry. But a certain level of delicate stability had been reached between the central government and tribal factions, one that seemed functional for that society, if not optimal. I also agree that it was certainly more stable in this period than Burma, Southeast Asia in general, or any of a number of African or Latin American nations. Decades of Cold War proxy battles and internal social disruption have bred anarchy. But I see no reason, theoretically, that this can’t be repaired ( as a practical matter it might be iffy, but it has to be tried ). Certainly the exhausted people of Afghanistan seem more receptive than ever to an attempt.
At any rate, I think it is a moot point. I rather boringly agree once again with tomndeb that the current direction seems the best choice. While it may fail, IMHO your idea would have no chance of success. The Afghans are far too xenophobic to ever tolerate that kind of enforced, “outsider” regime. The reaction would be violent and sustained. Whether it would be successful in tossing out the “invaders” is academic. The continued violence alone ( and its attendant factionalism ) would be enough to prevent the society from stabilizing and modernizing.
Just my $.02.
Re: The Kipling Hijack - I’m a fan. The Jungle Books was my favorite piece of literature as a child. That said, while I do think that compared to his countrymen he was indeed a lot less racist than most, I also think it would be fair to label him with the milder perjorative of paternalist. He was not, to the best of my knowledge, in favor of devolving British rule in India, he did think said foreign ( and extractive )rule was better for the natives, and he did seem to regard native peoples as a little “childish” compared to the more serious and competent English.
A further $.02 
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