President Trump met recently with Xi Jinping, the president of China, at the Group of 20 summit in Osaka, Japan. Their meeting carried an echo, the outcome resembling what the two produced last December in Buenos Aires at the same gathering of leading countries. They announced a truce in the trade war between their two countries. They pledged to resume negotiations.

Will this be the pattern, the world’s most formidable economies finding a degree of stability, jousting and then stepping back? That would not be the worst result. And yet, the hope is they will find a way to reach an enduring agreement, the president moving away from his tariffs as the Chinese open more markets and play more by the rules of international trade.

Recall how they got to the Osaka truce. A year ago, the president applied 25 percent tariffs on $50 billion a year in Chinese imports, including parts crucial to the auto industry. He then placed 10 percent tariffs on another $200 million in Chinese goods, eventually taking the levy to 25 percent. After negotiations faltered in May, the president threatened to apply tariffs to the remaining $300 million in annual Chinese imports.

China has responded with its own tariffs on American goods, inflicting perhaps the most pain on soybean farmers in Ohio and other states. Not surprisingly, the Chinese are looking elsewhere to buy such farm products. Which gets to a big concern about American farmers losing Chinese customers for the long term, something the $28 billion in federal assistance to beleaguered farmers cannot make up.

The Chinese, too, have felt pain, the trade barriers burdening a slowing domestic economy and threatening to spur eventual changes in supply chains, companies shifting their manufacturing to other countries.

So there is good reason to reach a comprehensive agreement, or at least avoid deeper trouble. In Buenos Aires, President Xi signaled a willingness to resume purchasing American agricultural products. Now he has done so again, President Trump describing the level as a “tremendous amount.” Will the purchases prove real and to what sum?

The Trump White House appeared to give ground on dealings with Huawei, the Chinese telecom powerhouse, viewed by many in American intelligence as a threat to national security. The thinking has been to limit sales to Huawei to keep the company from penetrating telecommunications systems. In Osaka, President Trump seemed to say the threat could be managed, allowing room for sales that do not put security at risk.

The confusing thing is that the president’s view runs against warnings his administration has delivered to allies and others in attempting to enlist them in an effort to isolate and protect against Huawei. Is it really possible to manage the sales as the president suggests? Analysts now worry he has all but abandoned the effort to check the company.

What might China deliver in exchange? That appears a matter ripe for resumed negotiations. It also gets to fundamental disagreements not easily overcome. There is little prospect of the Chinese altering the structure of their state-driven economy, or appearing to bow to American pressure. If that is what the president wants to see, and at times it seems so, his tariffs may be here for a long time, leaving him to threaten higher levies and then, hopefully, think better of bringing further disruption.

All of this risks the prolonged uncertainty that businesses do not like. It also leaves the way open still to a more promising approach. The United States isn’t alone in wanting China to uphold global trading rules. Build a coalition of countries to apply pressure. The president has China’s attention