President-elect Donald Trump has named retired Gen. James Mattis as his choice to be the next U.S. defense secretary.

That will require legislation because Mattis hasn’t been out of uniform for 7 years, a requirement if a military man is going to lead the Pentagon.

Trump has also been considering other former generals. So is Trump more focused on military men than his predecessors?

To learn more, we spoke with Daniel Rothenberg, co-director of the Center on the Future of War at ASU.