Diplomats in many other countries learned the secret to good relations with the United States years ago: Tell the Americans what they want to hear.

So the small victory President Donald Trump has won in the so-called “trade war” he initiated needs to be taken with a grain of salt. Time will tell whether he actually prevailed.

Nevertheless, the news from Beijing was good this week. Trump’s vow to slap higher tariffs on some Chinese goods in retaliation for unfair trade practices by that country seems to have paid off.

Initially, Chinese leaders reacted by saying they would hike tariffs on U.S. goods sold in their country. But on Tuesday, Chinese President Xi Jinping appeared to reverse course. He said he will reduce tariffs on cars imported into his country. That will help U.S. automakers.

Also, said Xi, China will address a longstanding U.S. complaint, intellectual property protection.

Good. Both moves are long overdue. They were among changes Trump had sought.

Whatever the outcome, Xi’s announcement was good news in that it seems to reflect a reluctance to engage in a tariff war.

Still, Americans should adopt a wait-and-see attitude. Is Chinese policy really changing? Or is Xi merely trading his promises for relaxation of the Trump tariff position? Will Beijing find different ways to harm the U.S. economy? If so, the reaction in Washington has to be swift and decisive.