It's the latest example in a pattern perfected by a chairperson whose actions have had the effect of diversion. Faced with an explosive political situation at his feet, he lobs a rhetorical grenade elsewhere, using the resulting detonation and confusion to his advantage. It moves the conversation from one that has him on defense to one where he is on offense.
When Trump made the unsubstantiated assert on Twitter that his predecessor had wiretapped him in the waning days of the 2016 election, it diverted attention from the growing body of undisputed reports that his surrogates and staffers had met with the Russian ambassador before and after the election. His campaign chairman was forced out over the summer after questions about his ties to Ukraine and Russia, his national security consultant was fired last month and last week came the news that his staffers and now-Attorney General Jeff Sessions met with Russians before the election.