BEIJING, April 9 -- When U.S. Treasury Secretary Janet Yellen dined at one of the oldest Cantonese restaurants Taotaoju after landing up in Guangzhou Thursday, the U.S. side demanded that the privacy screens be moved so that they could enjoy cuisine together with local diners sitting around.

Such a "remove-the-barrier" request, a gesture of openness that allows Yellen and her entourage to have a direct engagement with the Chinese people, was also a graceful pose for the camera. However, don't forget that there are formidable barriers hindering interactions between China and the United States, which wait to be dismantled for the good of the two nations as well as the rest of the world.

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