According to the NYT, agents and senior F.B.I. officials "had grown suspicious of Mr. Trump's ties to Russia during the 2016 campaign" but held off on opening an investigation into him, the people said, in part because they were uncertain how to proceed with an inquiry of such sensitivity and magnitude.
What happened next? Well, a collusion narrative was born and carefully crafted as the paper explains:
The president's activities before and after Mr. Comey's firing in May 2017, particularly two instances in which Mr. Trump tied the Comey dismissal to the Russia investigation, helped prompt the counterintelligence aspect of the inquiry, the people said.