There’s a line on the History Major page at the US Naval Academy:

Effective leadership is applied history.

Leadership, more than anything, is decision-making—specifically decision-making that affects other people, not only you.

By studying history, you can examine the minds of other leaders and understand their actions and the resulting outcomes (good and bad).

You can learn lessons from other people’s experiences rather than from your own failures and setbacks. This will not only save you time, money, and emotional labor—in some cases, it might save lives.

As General James Mattis said:

“If you haven’t read hundreds of books, you are functionally illiterate, and you will be incompetent, because your personal experiences alone aren’t broad enough to sustain you.”

Learn lessons from others by studying history. Don’t repeat their mistakes when you can simply read a book.