From the outset, President Trump’s refrain on the investigation of Russian interference in the 2016 presidential campaign and any coordination with his campaign has been consistent. Since May 2017 — shortly after Robert S. Mueller III was appointed special counsel to investigate the issue — Trump has tweeted some variant of “no collusion!” no fewer than 65 times. That refrain has been constant despite the evolving nature of the investigation, the myriad indictments and the sprawling assessments of who in Trump’s orbit knew what and when.