Fulton’s Folly was a steam driven boat on the Hudson River. Jefferson’s Folly was the Louisiana Purchase which included Loisianna, Arkansas, Oklahoma, Missouri, Kansas, Colorado, Iowa, North Dakota, South Dakota, Montana, Wyoming, Oregon, Washington, and Minnesota. That’s the equivalent of Manhattan for a few glass beads. Seward’s Folly was the purchase of Alaska, the largest state by far.
I’ll take folly like these anytime.