Excerpt:
The Assembly of Muslim Jurists of America (AMJA) issued a fatwa prohibiting offering aid to foreign troops in Muslim countries whether on the personal or the business levels. The assembly, made up of jurists and scholars in charge of issuing fatwas for Muslims in the United States and headed by Sheikh Salah al-Sawy, received several inquiries about the stance of Islam on business deals with coalition troops in Iraq or NATO forces in Afghanistan, especially companies that transfer foodstuffs and other supplies to military bases.
The question was posted on AMJA fatwa bank, reads: "Is it permissible to participate in taking food to the American and foreign soldiers working in Muslim lands?" and the answer is, "That would not be permissible, for that would be helping others in sin and transgression."