But over five years, as Japan opened more "transplant" factories in the United States, Japanese auto makers have not come close to the old limit.

The United Automobile Workers union, which once represented virtually every assembly worker in the United States and could shut down the entire industry, has failed to organize several transplant factories.

"If you want to know why, tour one of the new Japanese transplant factories going up here."

In the meantime, some Japanese machine tool companies have begun building "transplant" factories in the United States and have even joined the industry's trade association, he said.

Q. Would changing the value of the yen have any impact on Japanese "transplant" factories that manufacture in the United States?

So far, the car makers have only hinted about greater use of American parts in their "transplant" factories in the American Midwest.

Japanese companies vastly increased the number of American parts they purchased for cars produced in the United States at "transplant" factories, where cars now average more than 50 percent American-made content.

The nine Japanese transplant factories are scheduled to build roughly 3.5 million cars and trucks a year by the mid-1990's, up from 2.1 million now.

In 2010, Bob King hired Richard Bensinger to organize Japanese, Korean, and German transplant factories in the United States.

But cars built at transplant factories accounted for 11.4 percent of sales, compared with 7.9 percent in 1989.