On Monday morning, the Harry Potter author posted an essay on her personal blog entitled “On Monsters, Villains and the EU Referendum,” in which she made the case for Britain remaining in the EU.

The post begins with a powerful statement: “I’m not an expert on much, but I do know how to create a monster.” Rowling then goes on to explain how both sides of the campaign—Remain and Leave—have been “appealing to [voters] through our universal need to make sense of the world by storytelling and that they have not been afraid to conjure monsters calculated to stir up our deepest fears.”

Yet it is the Leave campaign, says Rowling, that is “benefiting from our widespread cynicism and, unsurprisingly, fanning it,” she writes, and goes on to poke holes in both its economic and political arguments. “We dramatically underestimate the amount of international investment we receive from the EU, while grossly overestimating how many laws it makes, how much it spends on administration and the number of EU immigrants in this country,” she writes.

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The writer highlights immigration as the center of “some of the nastiest arguments” in the campaign and warns against Britain following in the steps of the U.S.:

Look towards the Republican Party in America and shudder. ‘Make America Great Again!’ cries a man who is fascist in all but name…He has the temperament of an unstable nightclub bouncer, jeers at violence when it breaks out at his rallies and wears his disdain for women and minorities with pride. God help America. God help us all.