Unpopular new policy comes as midterms loom and control of Congress could be decided by several Michigan races

Every day $1bn worth of goods crosses the river dividing Detroit, Michigan, and Windsor, Ontario, two largely blue-collar US and Canadian cities that have come to act as one in the creation of North America’s auto industry.

News this week of Donald Trump’s escalating trade spat with Canada has everyone worried. Political and economic leaders and observers labeled the move an act of “hubris” , blamed Trump’s “ego”, and called the escalation “insanity”.

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A reminder that we are covering the latest out of Jackson Hole, Wyoming, where Kevin Warsh – the new chair of the Federal Reserve – will deliver his first speech as the head of the US central bank at the annual economic policy symposium.

As my colleagues note, Warsh is under pressure to provide clarity on how the Federal Reserve should handle with inflation if price pressures don’t abate.