An investigation which found he misled parliament over lockdown parties in Downing Street has put paid to any comeback ambitions. But resigning now means he avoids full blame for the government’s entrenched unpopularity and a probable election loss to Labour, which holds a 20-point lead in opinion polls.
Johnson can bide his time and see how it turns out for Prime Minister Rishi Sunak. He said he was leaving “at least for now” but still holds influence and could seek re-election in a safer seat.
Trump’s situation is the more complex of the two.
He is due to be arraigned in court on Wednesday on 37 counts relating to the FBI raid last August on his Mar-a-Lago resort in Florida over classified documents.
While Trump depicts legal proceedings against him as a “witch-hunt” and has pointed to small numbers of documents being found at properties linked to Joe Biden and Mike Pence from when they were vice presidents, there are new, important details in his indictment.
The files at Mar-a-Lago include national security documents, ones on nuclear weapons programmes among them.
Boxes of documents were found in a bathroom, behind a shower curtain, in a bedroom, an office, and a ballroom. Two instances are outlined where Trump was willing to show classified documents to people not meant to see them. He also allegedly directed the transportation and storage of the boxes.
Most counts in the case are under the Espionage Act, and evidence includes taped conversations, video and testimony from employees.
Trump had previously said he declassified all the material before he left the White House but an audio recording from 2021 has him saying “this is secret information” and “I could have declassified it. Now I can’t”.
Politically, there are dangers for Trump.
Court appearances will come during the primary season. There are primary rivals such as Chris Christie and Pence who are trying to present themselves as a change from Trump if the Republican party wants to leave him behind. Republican officials are being careful to attack the legal process against Trump rather than the allegations.
National security is usually an area of common approach between the US parties. Trump’s actions over defence documents would likely be a liability with moderate voters in a general election.
The legal challenge may help Trump secure the Republican nomination but leave him limping in a match-up with Biden.