The cavalcade of evidence in the Mueller report showing that President Donald Trump repeatedly sought to limit, discourage and end the investigation into his campaign's connections to Russia's interference with US elections may or may not fit the legal definition of obstruction, but it definitively demonstrates how Mr Trump has always done business.

The President's unique, norm-smashing way of doing his job is a reflection of his campaign promise to be the ultimate disrupter, the outsider who would "drain the swamp" and bust up Washington's chummy power channels.