ITAR (International Traffic in Arms Regulations) is a set of U.S. government regulations that authorizes the President of the United States to control the export and import of defense-related material and services. The regulations are described in Title 22 (Foreign Relations), Chapter I (Department of State), Subchapter M of the Code of Federal Regulations.
External links
full text (http://www.fas.org/spp/starwars/offdocs/itar/)
Until 1996–1997, ITAR classified strong cryptography as arms and prohibited their export from the U.S. The Department of State's objective in enforcing ITAR is to advance national strategic objectives and U.S. foreign policy via the trade controls.
There is evidence of ITAR interfering with international cooperation within space science, as noted by Deborah Bass in her Phoenix Mars Lander Blog.
ITAR controls, as well as separate policy concerns, have hampered international cooperation in development of the F-35 Joint Strike Fighter (JSF).