President Trump signed an initial trade deal with China on Wednesday, bringing the first chapter of a protracted and economically damaging fight with one of the world’s largest economies to a close. The pact is intended to open Chinese markets to more American companies, increase farm and energy exports and provide greater protection for American technology and trade secrets. China has committed to buying an additional $200 billion worth of American goods and services by 2021 and is expected to ease some of the tariffs it has placed on American products.

But the agreement preserves the bulk of the tariffs that Mr. Trump has placed on $360 billion worth of Chinese goods, and it maintains the threat of additional punishment if Beijing does not live up to the terms of the deal.“Today we take a momentous step, one that has never been taken before with China toward a future of fair and reciprocal trade with China,” Mr. Trump said at a ceremony at the White House. “Together we are righting the wrongs of the past.”