Trump 'seeing the walls close in': Ex-Republican presidential aide
President Donald Trump paints the Mexico border as an open gate for criminals, including rapists, terrorists, people with dangerous diseases and phony asylum seekers. (AFP / Jim WATSON)

David Gergen, a former Republican aide to several presidents, observed that President Donald Trump seems to be feeling the walls closing in around him.

During a Sunday CNN panel, Gergen agreed that the president had a stressful week as former "fixer" Michael Cohen's testimony implicated the president in several crimes and there was no denuclearization deal from North Korea. When it came time for Trump to return to the United States, he relished the attention of the far-right at the CPAC event.

"I think it's the man seeing the walls close in," Gergen said. "But I think underlying that is a view that on his part that maybe he will get through the [Robert] Mueller investigation with a reasonably clean bill of health. Nobody knows for sure yet."

Gergen turned the conversation back to Rep. Jerry Nadler (D-NY) and the Judiciary Committee, which will seek documents and information from at least 60 people tied to Trump. It was a committee chair that ultimately found that there was wiretapping going on. From there, the taps led to tapes, and that eventually brought down President Richard Nixon.

"These committees have a long history," Gergen said. "I think for the Democrats, the challenge is not to overplay their hands. You know, there are a lot of people in this country that say, listen, if Mueller didn't find anything, why the hell are we going to have more and more investigations? Aren't you just trying to -- isn't this just a fishing expedition? I think they have to be careful to lay out a persuasive case of why they're taking -- undertaking each one of these investigations."

Watch the full panel discussion below: