Many of the globe’s big shooters in government, business, the arts and media will assemble in Davos, Switzerland Tuesday for the start of the annual four-day World Economic Forum.

The political landscape they will review has changed dramatically since they gathered a year ago, due primarily to one leader who may or may not show up. That’s U.S. President Donald Trump whose attendance, as of this writing, was contingent on the absurd government shutdown drama being staged once again in Washington – the 19th shutdown “crisis” since 1976.

“Actually, throughout my life, my two greatest assets have been mental stability and being, like, really smart. ...I went from VERY successful businessman, to top T.V. Star to President of the United States (on my first try). I think that would qualify as not smart, but genius....and a very stable genius at that!”

Who would have believed it?

John Diefenbaker waggled his finger sternly across the aisle as he instructed the Liberal government of the day in 1968: “It is a long road that has no ash cans.”

While the provenance of Dief’s metaphor is obscure, his warning was clear. You think you know what you are doing, but don’t get so full of yourself, so convinced of the rightness of your course that you do not see the obstacles littering the road ahead.

Prime Minister Justin Trudeau and his present-day Liberals must surely understand the Chief’s message. Their 2017 has been full of ash cans.

The most frustrated politician in Ottawa these days has to be Andrew Scheer.

He has been leader of the opposition for six months, long enough to have moved out of the shadow of his predecessor, Stephen Harper, and long enough to put his own stamp on the Conservative party.