“It is almost impossible to conceive a scene of more horror and distress,” Mackenzie wrote in his diary. Looking out a window, Mackenzie saw an “immense column of fire and smoke.” He hastily dressed and ran the two miles into town, where the fire, spread by a strong southerly wind, was already out of control.

The British had taken control of the city less than a week earlier, and Mackenzie was stationed at a house outside the commercial center of the city. Two and half weeks after the general’s unsuccessful appeal, on September 20, a sentry awoke British Brigade Major Frederick Mackenzie with urgent news: New York was engulfed in flames. Refused permission by Congress, Washington and his army retreated from New York on September 15, leaving the city intact. Washington chose his words carefully, but he later made it clear that his wish before retreating was to see New York City-the second-largest urban center in the Thirteen Colonies, with a population of around 25,000-“laid in ashes.” He knew this plan would be controversial, so he urged Congress to be discreet in its response, writing, “If Congress therefore should resolve upon the destruction of, the resolution should be a profound secret.” “They would derive great conveniences from it on the one hand-and much property would be destroyed on the other.”

“If we should be obliged to abandon this town, ought it to stand as winter quarters for the enemy?” he asked John Hancock, the Congress’ president. The general knew his beleaguered Continental Army couldn’t hold the city against the world’s greatest navy, but as he prepared to retreat, he hoped to deny the British harbor through a strategy nearly as old as warfare itself: a scorched-earth policy. On September 2, 1776, George Washington wrote to the Continental Congress, seeking permission to burn New York City to the ground.

The incendiaries book