In true Donald Trump fashion, the president-elect kicked off a series of rallies in Cincinnati on Tuesday, returning to the format that served him so well in his campaign. Trump is calling it a “Thank You” tour aimed at showing appreciation to the core base of supporters who helped drive him to one of the most shocking upsets in American political history.

And in true Trump fashion, he surprised even his own transition team by making an unscheduled announcement: Marine General James “Mad Dog” Mattis would be his nominee for secretary of Defense.

“They say he’s the closest thing to Gen. George Patton that we have,” Trump said. “It’s about time.”

Trump acknowledged that he hadn’t planned to make the announcement until Monday. “So don’t tell anybody,” he joked.

If the timing of the announcement was a surprise, the choice was not. Gen. Mattis was widely considered the favorite for the job, despite the fact that he is not technically eligible to accept it under current federal law. A statute requires retired military officials to wait seven years before taking a civilian job at the Defense Department. Congress will need to grant Mattis a waiver if he is to be confirmed. According to Fox News, Republicans in the House and Senate are already putting that waiver in motion.

Though it is rare for a former military general to run the Department of Defense, Mattis’s battlefield record is a strong one. Along with leadership experience dating back to the first Gulf War, Mattis led Marine battalions into Afghanistan and Iraq in the aftermath of 9/11. By 2010, he was in charge of CentCom, calling the shots in both wars.

The AP spoke with Richard Fontaine of the Center for a New American Security, who was pleased with Trump’s nominee.

“He knows the Middle East, South Asia, NATO and other areas and has evinced both a nuanced approach to the wars we’re in and an appreciation for the importance of allies,” Fontaine said. “If he were to get the nomination, I suspect that he could attract a number of very talented people to work with him.”

Trump, who comes to the White House with zero military or political experience, needs to fill his cabinet with people who know what they’re doing. If a couple of his appointments raise questions on that point, this one does not. Mattis as Defense Secretary is a good move.