Why hasn't Japan's trade surplus against the United States been reduced?

Japan's trade surplus has long been criticized by the United States.
In the 1970s, textile products, color TV sets, and industrial machinery were the targets, while in the 80s, the targets of criticism were automobiles, semiconductors and VTRs.
In the 90s, the criticism turned to Japan's economic structure itself, saying it has been the major cause of the trade surplus problem.
Negotiations took place between the two countries based on the United States-Japan Framework Talks on Bilateral Trade launched in July 1993.
The talks have focused on the following three areas: reduction of Japan's trade surplus as well as the United States' financial deficit, negotiations concerning each product, and global cooperation.
However, even in the latter half of the 1990s trade frictions continued with regard to automobiles, semiconductors, and steel.