During the summer of 2013, Joe Biden’s oldest son, Beau, learned he had a glioblastoma, an especially ferocious and pitiless type of brain tumor. Biden told almost no one. His grief did not spill into open view. But eventually, the world came to know. Beau Biden — Iraq War veteran, former attorney general of the state of Delaware — died on May 30, 2015. He was 46.

Most civilians have the luxury, if you could call it that, of mourning privately. Biden did not. He repeatedly said that work was his salvation during that time, which wasn’t hard to believe. But you had to wonder about the nature of his dual existence. Every time he made a public appearance, there was another man entirely, a frightened or broken one, tucked inside the guy we saw on TV.

What’s most remarkable about Biden’s “Promise Me, Dad: A Year of Hope, Hardship, and Purpose” is that he’s decided to give us full visibility into the agony and strangeness of that period, showing just what it was like to care for his son — and then mourn him — while simultaneously fulfilling his duties as vice president. The book is a backstage drama, honest, raw and rich in detail. People who have lost someone will genuinely take comfort from what he has to say.

But this memoir is also a political book, one in which Biden touts his accomplishments and makes frequent forays into the wetlands of foreign and domestic policy. His position-paper entr’actes can be awkward and artless, much like the author himself. But after a time, you come to understand why he’s mixing in pages of his curriculum vitae with pages about grief: To Biden, the two are intertwined. It’s almost as if he suffers from a kind of political synesthesia. Deciding whether to run for the Democratic nomination in 2016, he writes, “was all tied up with Beau.”