The correct reason U.S. journalists referred to Catherine Curtis as the “most dangerous woman in America” is that she used her wealth and influence to recruit large numbers of women into her isolationist organization.
Curtis was known for her strong isolationist views and her efforts to rally women against U.S. involvement in foreign wars, particularly in the context of World War II. Her ability to mobilize female support for isolationist policies was seen as a significant threat to pro-interventionist sentiments at the time, which is why she garnered such a controversial reputation.