Asha Rangappa, the former FBI agent and regular CNN commentator, said Mr Trump hobbled the National Guard response to the riot to serve his political goals.
During her interview, CNN anchor Brooke Baldwin asked Ms Rangappa if Mr Trump's decision to stave off the National Guard was for the sake of optics.
"Is that even in the realm of possibility that optics could be a reason?" Ms Baldwin said.
"I think with the prior administration, it absolutely could have been in the realm of possibly, and that's a problem," Ms Rangappa said.
"So let just go back to what we mean by optics. The narrative that was pushed by the former president was that the existential threat to the republic was Antifa as manifested in these Black Lives Matter protests, and which warranted this heavy military and law enforcement presence which we saw in DC and elsewhere. So when they are concerned about optics, what I think they are suggesting is that they did not want a similar presence for the people who were coming to the Capitol in support of the president, because what would that say? That would suggest that they are as dangerous as the other threat that they have been hyping up for some time."
Ms Rangappa theorised that Mr Trump did not want images of police beating his supporters because it would resemble the footage of police beating Black Lives Matter and Antifa members over the summer.
"So optics, to me, means is that he (was) deliberately mitigating the threat and the perception of the threat, I think, in service of this greater narrative of where the danger really is," she said.
Ms Rangappa's comments come in the wake of testimony made to Congress by DC National Guard commanding general William Walker.
Mr Walker said he was "stunned" that the Pentagon officials from the Trump administration refused to send reinforcements to the Capitol for more than three hours, citing the "optics."
On the day of the insurrection, senior Department of Defense officials Charles Flynn and Walter Piatt advised military commanders that "it would not be their best military advice to have uniformed guardsmen on the Capitol," pointing to the optics and the fear that deploying the National Guard might inflame the rioters.
Mr Walker said that the National Guard was given immediate approval to respond to Black Lives Matter and George Floyd protests last summer.
Police bolstered security at the Capitol again this week to prepare for potential violence from QAnon adherents and conspiracy-minded Trump supporters who believe Mr Trump will return to power on 4 March.
On Wednesday, Capitol Police released a statement saying the department had "obtained intelligence that shows a possible plot to breach the Capitol by an identified militia group on Thursday, March 4."
The House of Representatives cancelled its session on Thursday as a precaution.