Speaking at a campaign event in Dover, New Hampshire, the author described an "illusion of choice," and criticized the "political media elite establishment. It's a corporate establishment."
"And they will not only tell us what we're supposed to talk about," she said. "They will tell us who we're supposed to choose to even choose between in terms of voting."
In a follow-up statement to The Associated Press, Williamson clarified that Iran was "a cautionary tale, not a direct analogy." She also said the July Fourth holiday "reminds us of our unique place in the world and the hope and light we represent to others."
However, she added, "When corporate forces begin to dictate our candidates and give us fewer and fewer choices, it is a threat to our foundation." She said all candidates should be welcome to participate "whether they are backed by monied forces or not."
Williamson is polling far below leading 2020 presidential contenders, though her debate performance late last month attracted some attention. She managed to make the June debate stage over more traditional presidential contenders like Massachusetts Rep. Seth Moulton and Montana Gov. Steve Bullock.