THE INCREDIBLE SHRINKING LEGACY: Goodbye to Barack Obama’s world.

Whatever precise form Mr Trump’s administration takes, we know this: Mr Obama’s legacy will be purged. In many cases all it will take is the stroke of Mr Trump’s pen.

The Obama erasure will go far deeper than undoing domestic laws, or foreign deals. Mr Trump will repeal Obamacare, or alter it beyond recognition. He will “keep an open mind” about whether to pull the US out of the Paris agreement on climate change and quite probably blow up the US-Iran nuclear deal. These acts would undo Mr Obama’s most visible achievements. Less obvious ones, such as the ban on Arctic drilling and enhanced interrogation techniques and the intention of closing Guantánamo Bay (never completed) will also be consigned to the dustbin. It will be as if Mr Obama was never here.

FLASHBACK: Clinton, Obama spar over Reagan.

Both Clinton and her husband have taken Obama to task for telling the Reno (Nevada) Gazette-Journal: “Ronald Reagan changed the trajectory of America in a way that, you know, Richard Nixon did not and in a way that Bill Clinton did not. He put us on a fundamentally different path because the country was ready for it. He tapped into what people were already feeling, which is we want clarity, we want optimism, we want, you know, a return to that sense of dynamism and, you know, entrepreneurship that had been missing.”

Obama will leave the White House with a resumé almost as thin as the one he came in with.

VOX’S TAKE IS CUTE, HOWEVER: Barack Obama is officially one of the most consequential presidents in American history.