The Philadelphia Inquirer has published an article on the AIA's efforts to preach to the troops not to purchase artifacts that are offered to them for sale by the local populace in places like Iraq and Afghanistan. See http://www.philly.com/inquirer/health_science/daily/20101126_Troops_headed_to_Iraq_get_lessons_in_ancient_artifacts_Iraq-bound_troops_get_lesson_in_ancient_artifacts.html?viewAll=y&c=y
The article commends a National Guard soldier for the "good move" of purchasing a copy Enfield Rifle from the locals rather than "old coins" or "bronze daggers" while on tour in Afghanistan. For more on "Khyber Pass Copy" weapons, see http://en.wikipedia.org/wiki/Khyber_Pass_Copy
I'm all for teaching respect for ancient cultures, but I doubt a "zero tolerance" policy on the purchase of minor artifacts does much to either win the "hearts and minds" of the locals or to protect cultural patrimony. If anything, old coins that do not find a purchaser will likely be melted as scrap in poor countries like Afghanistan. That would be a greater tragedy in my opinion than some farmer digging them up in the first place. To consider the destruction of context to be worse as the AIA preaches depends on the false premise that Afghanistan or Iraq will host extensive archaeological excavations again sometime in the future, which at this point seems ludicrous. [More likely, the areas where these artifacts are found will never be professionally excavated for lack of funds or interest.] Meanwhile, the AIA and groups like SAFE are strangely silent about the prospect of a Chinese mining company blowing up a significant cultural site in Afghanistan in order to tap a copper vein. See http://sciencereligionnews.blogspot.com/2010/08/ancient-monastery-in-afghanistan-under.html and http://phdiva.blogspot.com/2010/11/buddhist-monastery-in-afghanistan.html That to me seems like a much greater potential cultural property tragedy than a soldier purchasing old coins or other "bric-a-brac" as the Philadelphia Inquirer describes it.
I also find it disturbing that the AIA continues to claim there is a link between subsistence digging and terrorism, when that inflammatory claim is not based on much hard evidence. See http://art-crime.blogspot.com/2010/11/arca-student-kim-alderman-presents.html (interview with attorney associated with preservation community).
If anything, it's far more likely that the soldier's purchase of an Enfield rifle will help pay for the seller's upgrade to an AK-47. Remember folks out there, old coins don't kill; guns do.
Addendum: Recent disclosures about the scale of Afghan corruption gleaned from diplomatic cables released by Wikileaks adds an additional gloss on this issue. See
http://www.nytimes.com/2010/12/03/world/asia/03wikileaks-corruption.html?_r=1&scp=1&sq=cables%20afghanistan&st=cse It seems quite odd to promote efforts to preclude poor farmers from selling what artifacts they find on their own land at the same time that millions of aid dollars are leaving the country under suspicious circumstances.