David Petraeus is arguably the best known American general of the post-Vietnam era. He gained fame after leading the surge in Iraq, a controversial buildup of U.S. forces that was credited with a sharp reduction of violence during the American occupation. After retiring from the Army, he headed the CIA from late 2011 to 2012 and is now a partner at the private equity firm KKR. Petraeus has written about leadership and is known as a strategic thinker who emphasizes painstaking preparation.

During an appearance at a View From The Top session at Stanford Graduate School of Business in early April, he paraphrased a quote attributed to the Roman philosopher Seneca: “Luck is what happens when preparation meets opportunity.” Petraeus drew on lessons learned during his successful military career and his fall from grace at the CIA to share insights into leadership and personal growth.

Tasks of the Strategic Leader

There are four tasks that strategic leaders must master, whether they are in the worlds of business, intelligence, or the military, Petraeus says:

• Get the big ideas right.
• Communicate those ideas effectively.
• Oversee the implementation of the ideas
• Determine how to refine the big ideas — then repeat the cycle.

The fourth step, he says, needs to be undertaken as part of formal, structured process. “This isn’t something that you do while you’re running or in the shower or moments of reflection or something like that.” You have to actually sit down and do it, he says.

Be Prepared for Opportunity

Petraeus quoted Napoleon, who once said: “Every corporal has a field marshal’s baton in his rucksack.” The retired general took that dictum so seriously that he tied a swagger stick — he couldn’t find a marshal’s baton — to the frame of his own rucksack to remind himself to be ready to seize an opportunity. “You need to be prepared. You do it with a joke, try to be self-deprecating or whatever. But at the end of the day, in the back of your mind, it has to be that this actually could happen,” he advises.

Big Ideas Are Crucial

Under Petraeus’s command, American forces in Iraq were boosted by 25,000 to 30,000 troops. But the real strength of the surge wasn’t the larger combat force, he says. “It was the surge of ideas, the big ideas. Big ideas don’t usually hit you on the head like Newton’s apple, fully formed. You tend to get hit on the head by a seed of a big idea.” A good leader, he says, “will shape those big ideas inclusively because you want everybody feeling as if they’re inside the tent.” If they’re outside the tent, you won’t have their cooperation.

Tell the Truth to the Press

There were a lot of bad days for American forces and Petraeus when he was in Iraq. And when a bad day happens and it’s time to face the press, simply tell the truth, he advises. “When you have a horrible day, go out to the podium and say, ‘We had a horrible day.’” And there were days during his time in Iraq that were truly horrible. “They blew up a part of the Parliament. They dropped the old historic bridge right in the center of the Tigris River, and again blew up a mosque [whose destruction] touched off the violence the previous year.”

Own Your Mistakes and Setbacks

“Life isn’t full of high-five moments,” Petraeus says. Mistakes and “screw-ups” happen in organizations, setbacks happen to individuals. When the mistake is yours, acknowledge it publicly. Reflecting on his own history, he says: “Apologize for it if that’s required and, most importantly, determine how to mitigate the risk of this recurring in the future. Afterward you’ve got to remember that life goes on. And then you start figuring out, OK, what are the options? What is it that would be fulfilling, rewarding?”

Prepare for Bad Times

The current economic recovery from the great recession of 2008 is one of the longest in memory, so younger associates at his firm have never worked through a downtime, Petraeus says. So the question becomes: How do you prepare yourself for the difficult times? Getting ready for a downturn is a grinding experience, he says, adding that KKR may use war game-like exercises as a training tool. “I guess winter is always coming,” he says.