President Trump has tried using economic leverage over China as a way to coerce them into helping the U.S. with North Korea. It hasn't worked well so far, but Trump's optimism on securing China's help seemed to come back today when he tweeted about his "excellent meeting on trade & North Korea" with China's President Xi Jinping.
But Trump's tone on China changes month to month, and there's been a clear difference in his views on Twitter compared to what he says to President Xi in person.
Why it matters: Axios' Jonathan Swan points out Trump tried his charm on Xi — lavishing him in hospitality at Mar-a-Lago — but has already discovered that Xi cannot, or is unwilling to, do what's required to stop North Korea's rush to develop nukes — so now he's getting tough on trade with Xi. But his ever-changing tone could discourage Xi from cooperating.