What effect has disease had on the history of war, in particular the American Revolution? Traditionally, scholars have focused on the strategies of commanders with little concern paid to how illness impacted their decisions; Randolph G. Adams' work is a perfect example. More recent works have noted the power of disease and a few scholars, such as J.R. McNeill, have even argued that the consequences of illness were integral to the outcomes of historical events that helped shape the modern world.
The battle of Yorktown is, arguably, an example of both the tremendous influence of disease and the vital role of military strategy. British commanders knew that General Washington's army and the French fleet were on the move; they were also acutely aware of the havoc malaria could reek on their armies in the lowlands, especially during autumn. Yet, Cornwallis was ordered to remain in "sickly" Yorktown while General Clinton lingered in New York. .
The British were consciously negligent in regards to both Washington's movements and the effects of disease. But even J.R. McNeill's brilliant insights into malaria miss the full scope of disease's impact on the British army; small pox infected many of the former slaves that Cornwallis utilized for building his fortifications.6 Even if one excludes disease, Cornwallis's position at Yorktown was extremely bleak; but it is clear that illness, from both small pox and malaria, assisted the Americans in their victory. .
In "Yellow Jack and Geopolitics: Environment, Epidemics, and the Struggles for Empire in the American Tropics, 1650-1825," J.R. McNeill argues quite convincingly that empires "sowed the seeds of their own destruction." He states that yellow fever and the mosquitos that carry it were brought to the Americas via slave ships. Ironically, the very industry the slaves were brought over to work in, sugar production, provided the mosquitos with the perfect breeding habitat.