President Biden knows full well Vice President Kamala Harris is “not up to the job” of commander-in-chief — and he preferred Michigan Gov. Gretchen Whitmer as his running mate in 2020 before caving to public pressure, according to a new book out Tuesday. Biden chose Harris days before that year’s virtual Democratic National Convention after promising to select a woman and after pro-Harris lobbying from former President Barack Obama, veteran Washington journalist Charlie Spiering writes in his book “Amateur Hour: Kamala Harris in the White House.” While the 59-year-old Harris is just “a brain stroke away from the presidency,” her...