Thaddeus Kosciuszko, a Polish-Lithuanian born in 1746, was one of the most important figures of the modern world. Fleeing his homeland after a death sentence was placed on his head (when he dared court a woman above his station), he came to America one month after the signing of the Declaration of Independence, literally showing up on Benjamin Franklin's doorstep in Philadelphia with little more than a revolutionary spirit and a genius for engineering. Entering the fray as a volunteer in the war effort, he quickly proved his capabilities and became the most talented engineer of the...