The title of Kamala Harris’s new book, “107 Days,” hits the reader on the head with a central argument about why she lost the presidential race to Donald Trump. “I didn’t have enough time,” she wrote.

Not enough time to craft a message that broke through to the economic concerns of Gen Z and Latino voters who helped sway the election in Mr. Trump’s favor. Not enough time — or, she wrote, enough help from President Joseph R. Biden Jr. and his team — to combat a right-wing media apparatus that tore into her. Not enough time to warn Americans that Mr. Trump was serious about attacking democratic institutions, crushing dissent and unraveling delicate diplomatic bonds.

All the while, she was juggling a compressed campaign and trying to figure out how to counter Mr. Trump, an opponent who publicly attacked her in personal terms but praised her profusely in private. She should have done more to strategize against him, she wrote.

In the book, Ms. Harris was more interested in assigning blame to Mr. Trump for the current state of politics than to Mr. Biden, herself or other Democrats. And she left open the idea that she would return to politics in the near future.

Here are five takeaways from the book:

Trump attacked her in public and praised her one-on-one.

Mr. Trump can be solicitous when the cameras are not rolling, and Ms. Harris experienced this side of him on two phone calls she detailed in the book.