The opium trade helps fund the insurgency but also provides farmers livelihood.
Ethiopia confirmed this week that it will pull troops out of the troubled nation, a move that experts worry could allow the country to fall into the hands of Islamist insurgents.
Insecurity and charges of fraud could hamper election officials' ability to ensure popular acceptance of next year's presidential poll results.
In addition to monitoring the volatile border region between Israel and Lebanon, the peacekeepers build roads and teach foreign languages to locals.
Defense officials say it will fill urgent gaps but Special Forces officers are skeptical.
But critics say the US should go slowly on a deal that would help a crucial trading partner for Iran.
Monday's attack came amid discussion of doubling the US forces in Afghanistan by mid-2009.