Donald Trump is unfit to be President. His Presidency is a sham and his election might be the greatest con ever played.

The common factor in all these situations is Trump’s self-induced powerlessness and ignorance, his chronic lack of credibility and presidential authority and consequent perceptions of US and western weakness. And in the case of all three actual or potential adversaries – North Korea, Iran and Russia – these perceptions are highly dangerous. Precisely because US responses, actions and reactions can no longer be relied upon or predicted, by friends and enemies alike, the potential for calamitous miscalculation is growing. This uncertainty, like the chaos in the White House and the extraordinary disarray of the American body politic, stems from Trump’s glaring unfitness for the highest office. As is now becoming ever plainer, this threatens us all.

His incompetence and unpredictability are the traits that keeps me up at night.