Washington's own policy was a formal and circumspect neutrality, despite French and British attacks on Yankee ships and the British impressment of American seamen.
Roosevelt and Churchill worked differently: the president was circumspect, restrained and cagey, while the prime minister was effusive, commanding and far more experienced in military affairs.
The authors are meticulous in the details they recount, although the tone can feel uneven, at first boosterish when discussing the gun's origins before becoming more circumspect.