Slavery was necessary for the United States’ cotton boom because productivity levels were not high enough to attract free labour.
The dominant view among economic historians is that American slavery was an unnecessary evil: nothing good came of it for the development of the United States after independence. Even if some reluctantly accept that the boom in cotton production may have had some benefits for Antebellum America, they argue that the cotton could have instead been produced by free labour. Here, however, I will argue that productivity levels were too low in cotton to attract free labour, so slave labour was a necessary evil for the cotton boom.