Assistant Secretary of State Richard Holbrooke said yesterday that Sino-American relations since normalization "are good and steadily improving" and forecast that China over the years would emerge as a global economic and political power.

In an address to the annual meeting of the National Council for U.S.-China Trade, Holbrooke -- the State Department's top man for East Asian and Pacific Affairs -- predicted a real annual growth rate of 6 percent to 7 percent for China during the rest of the century.

That would mean that China would achieve by the year 2000 an economy -- in real terms -- about the size of the United States in the late 1970s.

Holbrooke said that this would be "an impressive achievement," creating a China to be reckoned with in world affairs.

"And, if China can overcome the bureaucratic inertia and difficulties inherent in managing the destinies of a billion or more people -- admittedly a very big "if -- it will have achieved a degree of security and capacity for independent action that it lacks today," he added.

Separately, the U.S. Export-Import Bank said it is ready to start approving loans to China on a case-by-case basis for the purchase of goods and and services. Already, Holbrooke said, U.S.-China trade will exceed $3 billion this year, or about three times the 1978 volume.

The National Coucil is a private organization founded in 1973 to facilitate trade, following President Nixon's reopening of relations with mainland China. Yesterday, the councl elected David S. Tappan Jr. of the Fluor Corp. as its chairman, succeeding John C. Brizendine of Douglas Aircraft Co.

Holbrooke's speech -- to an audience of leading American businessmen with a sprinkling of Chinese officials in attendance -- set out more specifically than had been done before the basic principles governing U.S. policies "for the decades to come."

He stressed that relations would "no longer be a simple function of our relations with the Soviet Union" but would develop on their own merits. In the absence of "frontal assaults on our common interests, we will remain -- as at present -- friends rather than allies," he said.

As before, Holbrooke ruled out the sale of arms to China or joint military planning with the Chinese but promised to "assist China's drive to improve its security by permitting appropriate technology transfer, including the sale of carefully selected items of dual-use technology and defensive military support equipment."

The Chinese relationship won't be pursued "at the expense" of others, including Taiwan, he said.

As to the Chinese effort to modernize its economy, Holbrooke stressed not only the usual elements of trade and economic exchange but also help in the fields of science and technology so that China doesn't "fall still further behind its more advanced neighbors."

Finally, Holbrooke said that the U.S. would pursue an effort to involve China in "global efforts to address the common problems of humankind."