WASHINGTON — President Trump is confident that the United States is winning its trade war with China. But on both sides of the Pacific, a bleaker recognition is taking hold: The world’s two largest economies are in the opening stages of a new economic Cold War, one that could persist well after Mr. Trump is out of office.

“This thing will last long,” Jack Ma, the billionaire chairman of Alibaba Group, warned a meeting of investors on Tuesday in Hangzhou, China. “If you want a short-term solution, there is no solution.”

Mr. Trump intensified his trade fight this week, imposing tariffs on $200 billion worth of Chinese goods and threatening to tax nearly all imports from China if it dared to retaliate. His position has bewildered, frustrated and provoked Beijing, which has responded with its own levies on American goods.

The diplomatic stalemate has many in the business and policy communities considering the possibility that the United States may be in a protracted and economically damaging trade fight for years to come and wondering what, if anything, America will gain.