( CNN) If President Trump genuinely did ask James Comey to aim the inquiry into national security adviser Michael Flynn — as the former FBI director is said to have claimed in a memo — then the United States has reached a rare tipping degree, David Gergen mentioned Tuesday night.

“After watching the Clinton impeachment I supposed I’d never consider another one, but I think we’re in impeachment province now for the first time, ” he told Anderson Cooperduring a live CNN appearance.

Gergen, who advised two US Presidents who faced impeachment process — Richard Nixon and Bill Clinton — mentions it shows Donald Trump was intentionally trying to influence the direction of the FBI’s probe into Flynn.