The ordinarily decisive George Washington was paralyzed by indecision. It was the summer of 1776, and the Continental Army was being routed by the British in New York. Sick from dysentery and smallpox, 20 percent of Washington’s forces were in no condition to fight.

Militia units were deserting in droves. General Washington had exhausted himself riding up and down the lines on Brooklyn Heights, attempting to rally dispirited troops. Prudence dictated retreat — to preserve the hope of fighting another day. At the same time, though, Washington viewed any defeat as damage to his reputation and a stain on his honor.

There are any number of good reasons to read Joseph J. Ellis’s splendid little book, Revolutionary Summer: The Birth of American Independence. Ellis is a wonderful storyteller. His prose is lucid and succinct. Revolutionary Summer is a riveting exposition of exploded myths and excruciating dilemmas. For one thing, Washington — while by no stretch of the imagination the “little paltry Colonel” the British constantly derided — was not the near deity we often read about in American history books. He only reluctantly accepted the advice of aides for what turned out to be a brilliant tactical retreat in August of that summer, and a turning point in the war.

Indeed, the Americans, writes Ellis, were frequently “improvising on the edge of catastrophe.” Which helps to explain why Ellis’s book is a such a terrific case study in leadership. Here are the lessons I take away from it for leaders today.

First, success often depends on a team with complementary skill sets, frequently involving different temperaments and work styles. As a leader you have to assemble the talent you need, and live with and mitigate the shortcomings of respective team members. Thomas Jefferson, drafter of the Declaration of Independence, was superb with a pen. He was a notoriously poor public speaker, however. John Adams was brilliant, courageous, and resolute. He also suffered extreme mood swings and could be dangerously hubristic. (Furious over desertion rates, Adams suggested to an aide that they execute in each regiment every tenth man as a lesson.) Then there was Thomas Paine, the perfect spokesman for their cause. “I could not reach the Strength and Brevity of his style,” remarked Adams, “nor his elegant Simplicity nor his piercing Ethos.” Yet Adams also contended that Paine was “better at tearing down than building up,” a reference to what would happen after British rule.

The takeaway? If you are clear about your objectives, and focused on precisely what you need to develop and execute the elements of your strategy, you can assemble an unbeatable organization. Hire for common purpose, yes. But don’t hire clones.

Second, leadership is tested most by a dilemma — a situation that requires a choice between two or more equally unfavorable options. It is leadership’s job to arrive at decisions, and to do so in a way that aids their implementation. Adams insisted on postponing deliberations on what the new nation would look like, fearing that early splits between advocates of a confederation of sovereign states and champions of a consolidated union would undermine the war effort. He also wanted to postpone discussion of the fundamental disagreement between the northern and southern states over slavery. Some 500,000 individuals, roughly 20 percent of the population at the time, were African American, and nearly all slaves. The institution of slavery was an appalling contradiction of everything the revolution stood for. But Adams was convinced that all other political goals would be lost if independence from Britain were not first achieved. (Adams also resisted his wife Abigail’s plea to advance rights for another disenfranchised group: the female population that could neither vote nor, if married, own property.)

Here, my takeaway is that essential to leading is being clear about priorities. Not all decisions will involve the profound moral dilemmas faced by Adams and his peers. However, every difficult decision has a downside and produces unintended consequences, some of which are simply impossible to foresee. Do your due diligence. Then plunge in and push ahead.

Finally, a gem nearly all of us ignore: good leaders need good sleep. There were many challenges that plagued George Washington. His soldiers were, writes Ellis, “a motley crew of marginal men and misfits, most wearing hunting shirts instead of uniforms, spitting tobacco every ten paces.” The array of considerations Washington had to make was daunting. To mention but one, there were roughly 15,000 cattle, sheep, and horses on Long Island. What to do? Leave them? Confiscate the livestock to prevent them from falling into British hands? If yes, how would confiscation impact the allegiance of the farmers? New York was already infested with loyalists. Washington was swamped by a thousand such details. One wonders, though, whether a chronic sleep deficit was as serious a challenge as any individual issue he faced.

According to Ellis, at one point Washington was so exhausted he was unable to file a crucial report to the Continental Congress. He told John Hancock that in 48 hours, “I had hardly been off my Horse and never closed my Eyes, so that I was quite unfit to write or dictate.” Was a lack of sleep at least in part responsible for Washington losing his customary discipline and control on the battlefield? At the battle of Kip’s Bay — between what is now 32nd and 38th streets in Manhattan — Washington “struck several officers [with his riding crop],” repeatedly threw his hat to the ground, and initially resisted his staff’s desperate efforts to get him to exit the field — as British infantry was just 50 yards away.

There’s nothing weak or wimpy about getting rest, even — and especially! — in crisis situations. Today we have the science to back this up. Sleep deprivation can produce myriad deleterious effects, including frustration, confusion, irrationality and indecisiveness. According to sleep researchers, sleep helps us with alertness, perception, memory, reaction time, and communication. Specifically, sleep deprivation diminishes regional cerebral metabolism in the prefrontal cortex, that part of the brain responsible for higher-order cognitive processes. The result: impaired judgment, and high-risk behaviors.

I myself recall managing the case of a kidnapped Iraqi journalist in Baghdad several years ago. Our team got the reporter out alive, with high marks in a review from the U.S. military hostage negotiators who had assisted throughout — except that I was criticized sharply for going two weeks on 3-4 hours sleep per night. That was a well-intentioned behavior that might well have put the entire operation in jeopardy, the de-brief emphasized.

The lesson should be obvious: Balance is key. Work like a maniac, if you will. But no matter the stakes, if you don’t rest your body and mind, something (or someone) will be jeopardized.

I’ll end with my most general (and perhaps obvious) takeaway from reading Ellis: leaders looking for insights on how to do their crucial work better will find them in the vivid accounts of past triumphs. We don’t read history because it repeats itself. We study history because it reveals and inspires.

And all the better if it sometimes amuses. When the commander of British forces, still hopeful for early surrender, told Benjamin Franklin that he would lament American defeat like the loss of a brother, Franklin replied, with a bow and a smile: “My Lord, we will do our outmost to save your Lordship that mortification.”

This blog first appeared on Harvard Business Review on 7/03/2014.

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