The CS-4 project was a series of
satellites
A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scientif ...
that Japan's
National Space Development Agency
The , or NASDA, was a Japanese national space agency established on October 1, 1969 under the National Space Development Agency Law only for peaceful purposes. Based on the Space Development Program enacted by the Minister of Education, Culture, ...
planned to launch from 1995 onwards.
The CS-4 series was described by Tomifumi Godai, one of NASDA's executive directors, as "an engineering test satellite . . . to develop communication technology with antennas of various bandwidths".
The project was announced as cancelled in 1990, after the
US Department of Commerce
The United States Department of Commerce (DOC) is an executive department of the U.S. federal government. It is responsible for gathering data for business and governmental decision making, establishing industrial standards, catalyzing econo ...
described the series as conventional communications satellites which could be used by
Nippon Telegraph and Telephone
(NTT) is a Japanese telecommunications holding company headquartered in Tokyo, Japan. Ranked 55th in ''Fortune'' Global 500, NTT is the fourth largest telecommunications company in the world in terms of revenue, as well as the third largest pu ...
instead of buying satellites on the open market. As that market was dominated by the US, they threatened to impose punitive tariffs on Japanese goods.
This was possible due to the "Super 301" clause of the
1988 Trade Act, which threatens retaliation against unfair trading.
Godai responded by saying the CS-4 had no commercial use, with NASDA merely developing the technology with no intention of selling it. Even after Japan said that it would allow foreign suppliers to bid for commercial satellite contracts, the program was still dropped.
References
Satellites of Japan
{{Japan-spacecraft-stub