The 70mm Curse

http://www.strategypage.com/htmw/htairw/articles/20091209.aspx

December 9, 2009: For a decade now, there have been numerous efforts
(at least ten) to turn 70mm (2.75 inch) rockets into laser guided
missiles. Recently, one of the newer efforts (GATR, by ATK/Elbit)
successfully fired their missiles from a standard 70mm unguided rocket
launcher. Two years ago, one of the American missiles, DAGR was
declared ready for service, but the U.S. Department of Defense didn't
respond with any orders.
DAGR (and its competitors) would appear to be an ideal weapon, as most
also use the Hellfire fire control system.