COLORADO SPRINGS – She’s faced down North Korean missiles and Russian bombers. The worst hurricane season in decades and raging wildfires couldn’t make her flinch. It takes a lot to scare Gen. Lori Robinson, who has led the North American Aerospace Defense Command and U.S. Northern Command through one of the busiest times.

But, what’s happening Thursday at Peterson Air Force Base is something she finds daunting, if not terrifying: retirement.

She’s ending a 36-year Air Force career. For the first time in her adult life, Robinson won’t have to worry about America’s defense. After a few final salutes, she’s off to a boat and a beach.

Thursday morning, with Defense Secretary James Mattis presiding, Robinson will hand off her leadership role to Air Force Gen. Terrence J. O’Shaughnessy, who comes to the new job after leading Air Force efforts in the Pacific and Asia.

She wants Thursday to be a celebration of O’Shaughnessy’s achievement in reaching the top rather than something that marks the end of her career.

“This is all about the new guy and setting the conditions for Gen. O’Shaughnessy to make sure he succeeds,” she said, “He’s earned it.”

Making way for the new guy is a hard shift for Robinson, America’s highest-ranking woman in uniform and the first woman to lead one of the nation’s major commands. After an unplanned military career led to her meteoric rise, retirement seems like falling off a cliff.

“It is a little eye-opening,” she admitted.

It’s not that Robinson is frail in the face of tough decisions.

Last year, she had to decide whether to risk Navy ships in the path of a hurricane to deliver rapid assistance to Puerto Rico or to move them to a safer location to make sure they could deliver help. The move cost time, a critical element in a crisis. But not making the move would have jeopardized the vessels.

“How can you ensure you don’t do more damage by leaving it there?” she asked.

Robinson moved the ships, and the assistance arrived, later but safer. She took some criticism; it rolled off her back.

Robinson earned that tough exterior. She joined the Air Force in 1982 after giving up her dream of becoming a teacher. An air battle manager, she learned how to orchestrate the sweeping attacks by scores of planes that were first on display in the Persian Gulf War.

She was a woman in a field dominated by men. It didn’t bother Robinson, she treated her comrades as so many big brothers.

Managing air battles is a cerebral field that requires officers like Robinson to translate a two-dimensional radar screen into a three-dimensional understanding.

“As an air battle manager, I had the ability to see things from a theater view versus a cockpit view,” she said.

Robinson proved she had plenty of brains for the job – in addition to her Air Force educational accolades, she’s earned a pair of master’s degrees, worked at a Washington, D.C., think tank and won a fellowship at Harvard.

While brain power matters, leadership wins battles. That a skill Robinson had in spades, with squadron, wing and group commands on her resumé along with a pair of Bronze Star Medals and three Distinguished Service Medals, the highest Air Force honor for service not involving combat.

Robinson says her rack of medals and other honors stem from serving with great troops.

“They’re awesome,” she said,

Robinson said she’s seldom had better subordinates than the crew she led at the Colorado Springs command, which scans the skies above the U.S. and Canada for threats and offers Pentagon support for disaster relief efforts across the United States.

Robinson said the universal trait at NORAD and Northern Command is a laser-like focus on defending the continent.

“Every single person realizes what a sacred responsibility it is,” she said.

That’s part of what has Robinson dreading retirement – that responsibility is only growing with rising threats.

In the past two years, she’s had to stay on call 24 hours a day.

“I tell everybody I sleep with my cellphone,” she said.

It rang at night many times, due in part to North Korean dictator Kim Jong Un’s missile tests, nuclear tests and threats to lob a warhead at American shores.

Robinson is optimistic about White House efforts to broker a deal with North Korea that would ease nuclear tensions. But Kim Jong Un, for now, is a top threat.

“He has tested very quickly,” Robinson said. “He has increased his capability very quickly.”

The other issue that kept Robinson up at night was a string of unprecedented natural disasters. Ten hurricanes, including Harvey which deluged south Texas, Maria, which wrecked Puerto Rico and Irma, which slammed the Virgin Islands, taxed the command’s resources as the military rushed medical aid, food, water, and other resources to back up civilian authorities.

The command was simultaneously coordinating military help in battling wildfires that blackened more than 10 million acres across the country in 2017.

Robinson said the command learned form the fires and floods.

“It was a lot of good lessons,” she said.

In all roles, Robinson said NORAD and Northern Command must be ready to react quickly and adjust for change.

“The world doesn’t stand still,” she said.

Being in charge in such troubled times cost Robinson plenty of sleep, but she has no regrets.

“These two commands are incredibly complex, but they serve a common purpose,” Robinson said. “To have had the privilege of commanding them both is an absolute honor.”

She’s accepting the fact that her time at the top of those command is ending.

She’s found aspects of the change that she’ll cherish.

“I’m looking forward to spending time with the kids and the grandkids,” she said.

To get ready for the ceremony Thursday, Robinson went through old pictures. They ranged from her childhood to her career. Each new rank was documented. Every step came with an image.

That’s part of why looking forward is so tough.

“When I sat back and I’m looking over from when I was a baby on my dad’s lap, I feel like I’m the luckiest person in the world. I just hope I made a difference.”