Some desperate [terrorists] decided to [destroy American cities]. The idea was to ... team up with disaffected [locals] to wreak havoc. For New York City the plans were particularly grandiose. [Terrorists] would infiltrate the country from Canada, make their way to the metropolis, and set off fires around town.As you can tell, I’ve selectively changed a few words from this passage. The “terrorists” were not crazy Muslims but Confederates agents. This wasn't last week but 1864. Despite extensive property damage, the fires were extinguished and the city didn’t burn down.
[Terrorists] would revenge the [destruction of their land] by ravaging [America], beginning with gay, rich, and carefree New York City. They would start by incinerating the opulent symbols of the city’s wealth, its glittering hotels. With luck, and a good wind, they might burn New York to the ground.
On the night of November 25, the conspirators set their fires in thirteen major hotels, chiefly along Broadway, including the Astor House, the Metropolitan, and the St. Nicholas... For good measure, the [terrorists] kindled would-be conflagrations in Barnum’s Museum, Niblo’s Theater, the Winter Garden, and assorted Hudson River docks, lumberyards, stores, and factories, before making good their escape to Canada.
As blazes broke out all along Broadway, terrified crowds poured in the street. Police wagons and fire engines fought their way through dense crowds of people screaming, “Find the rebels! Hang them from a lamppost! Burn them at the stake!”
A year later, just one conspirator, Robert Kennedy, was caught, tried as a spy, and hanged. The other conspirators escaped justice. I had never heard of this plot to destroy New York. It goes to show that modern-day terrorism is not just some new-fangled Islamic invention.
The passage is from pages 902 and 903 of Edwin Burrows and Mike Wallace’s excellent (and pre-2001) Gotham: A History of New York City to 1898. This book is shocking long (I don't think I've ever been on page 900 of a book before) and amazingly good.