As Robert Frost famously wrote, “Something there is that doesn’t love a wall.” Does Donald Trump agree? Is Trump really about to make a deal with Democrats to preserve the right of undocumented Dreamer adults who were brought to this country as children to remain here under DACA? It sure seemed so at Tuesday’s White House bipartisan love fest.

But other officials were quick to walk it back, giving Trump room to change his mind or demand a wall that hardly anyone in either party wants. On NPR’s Morning Edition, White House legislative director Marc Short redefined a “clean DACA bill” as including the administration’s other three top priorities. These are an end to “chain migration,” otherwise known as reunification of families and an end to the visa lottery—and, inevitably, “border security,” defined as a “physical barrier.” Short conceded Trump’s wall could be a “fence” in some places, because it’s actually useful to see what’s on the other side.

So what’s Trump really up to? Nobody really knows, not even Trump, whose moods change faster than the weather. On Tuesday it looked as if he wanted to posture bipartisan and humanitarian. Viewers were treated to the kind of live negotiating session that usually goes on behind closed doors.

But the end game is anyone’s guess. Conceivably, Democrats could trade permanent normalization under DACA for an end to the visa lottery and even for a toughening of rules on reunification of families. But the wall continues to be a nonstarter, and if Trump’s idea of a deal is DACA for the wall, it’s no deal.

One other detail: The adviser who was absolutely obsessive on the subject of the wall as a symbol of Trump’s tough anti-immigrant posture was … you guessed it: Steve Bannon. Maybe, with Bannon gone, Trump can give up the wall. With his embrace of the Dreamers and his declaration that he’s willing to take the heat from the far right, he’s already given up his pose as pure immigrant-basher.

Of course, that could change tomorrow depending on what Trump sees on cable TV and in Twitter world, and on Trump’s mood. Even Frost ended that celebrated and ambiguous poem with the words, “Good fences make good neighbors.”