The triumph of Trump was no less a surprise than Obama’s four years ago. That Americans have handed power to a foul-mouthed and potentially dangerous magnate is as unbelievable as was their electing a Kenyan Muslim’s son four years ago, even though he had gone to top universities. Seen in perspective, Newton’s Third Law – of action followed by reaction – has again held true, and it remains to be seen whether this play of balances does not end up disarranging the system altogether. Meanwhile, the turn-taking in power is also manifested in architecture. On his personal initiative, two grands projets will make up Obama’s architectural legacy. One, a presidential library in Chicago, has been commissioned to the New York firm Billie Tsien Architects, perhaps to compensate for the demolition of their most important work, the facade of the American Folk Museum. Even more personal was the decision to task David Adjaye – an African architect as educated and cosmopolitan as Obama himself – with the construction, in the capital, of the National Museum of African American History, which now stands in the National Mall, right between the Washington Monument and the White House, the country’s most symbolic spot. For the time being, the real estate mogul Trump has nothing to show for but the hotel opened shortly before his victory and standing just a short distance from Adjaye’s pyramid, but it is an omen of more pharaonic edifices to come, and of useful structures like the promised Wall that brought him so many votes and about which, right now, he prefers not to remember.