Here’s a real thing the president of the United States tweeted on Tuesday afternoon. It is about North Korea — and it is very, very hard to figure out what it means:

While I greatly appreciate the efforts of President Xi & China to help with North Korea, it has not worked out. At least I know China tried! — Donald J. Trump (@realDonaldTrump) June 20, 2017

You can sort of try to piece together what Trump might have meant.

It seems like he’s declaring failure in some kind of campaign by China to help the United States bring North Korea in line on issues of mutual concern, like the nuclear program and Otto Warmbier (the American who died this week shortly after being released from a North Korean prison camp).

Trump, who used to blame China for North Korean misbehavior but changed his mind after a 10-minute chat with Chinese President Xi Jinping in April, seems to be exonerating his new buddies in Beijing from any culpability in Warmbier’s death or North Korean ongoing missile tests.

But it’s not clear that China actually has done all that much to solve any of the various problems Kim Jong Un creates. They’ve done a bit, like ramping up criticism of the North in state-run media outlets, but that hasn’t caused Kim to change course on any major issue (at least, as far as we can tell).

China has a powerful tool at its disposal: its trade ties with Pyongyang. China is the North’s only major trading partner, so a threat to limit commerce if North Korea doesn’t change would be the natural way to try to push Kim around. Yet trade between China and North Korea actually increased in the first quarter of 2017, suggesting Beijing isn’t seriously trying to use economic pressure.

That would suggest that Trump has been completely snookered by Xi: reversing the simplistic anti-China stance he took during the campaign to an equally simplistic pro-China stance after meeting with China’s leader.

More importantly, this is only one speculative interpretation of what Trump’s tweet meant.

His wording is so imprecise, the policy implications so unclear, that it’s possible to read it as saying all sorts of different things. You could even interpret it as a threat — as Trump declaring that diplomacy with North Korea has failed and that a possible military strike on the Kim regime is now in play.

This kind of murkiness is dangerous. North Korea’s government is famously insular; it’s unclear how well they understand signals coming out of Washington. This tweet almost certainly doesn’t represent the start of some kind of new North Korea policy — but who knows if it’ll seem that way in Pyongyang?

The risk is that this kind of confused, potentially threatening message makes the North feel even more insecure — causing them to lash out even more with provocations like new missile tests.

It’s not that this tweet itself will spark a direct military response from the North. It’s that it adds to a background context of a rudderless, at times very belligerent, line on North Korea from the Trump administration. Sending vaguely threatening signals like this could create a level of tension that you really don’t want with a rogue, nuclear-armed power.