Actor George Takei compared President Trump to "an alien life form" who is ignorant of important issues like race relations.
Takei was discussing the newest "Star Trek" reboot, which he said has come under criticism because it lacks caucasian leads.
"Today, in this society, we have alien life forms that we call trolls," Takei said on MSNBC.
"And these trolls carry on without knowing what they're talking about... and some of these trolls go on to become presidents of nations," Takei said.
Takei said Trump is no different than the "trolls" who have criticized "Star Trek's" more diverse cast.
He said Trump's travel ban orders show ignorance of history, as some Trekkies' outcry shows ignorance of the program.
He compared Trump's order to President Franklin Roosevelt's 1942 dictate that led to Takei's family being interned in an American prison camp.
Takei said both Roosevelt and Trump's orders embodied fear of "the other."
"I think the president is as foolish and as uninformed and as ignorant as these trolls are," he said.
In another interview, Takei repeated his comparison to FDR, adding that Trump's presidency is "one chaos after another disaster."