When “Hillbilly Elegy” author JD Vance repeatedly attacked “childless cat ladies” and “childless Democrats” in 2021 and 2022, he was met with some scathing criticism in liberal and progressive publications. But it wasn’t a huge controversy. But now that the Ohio senator is Donald Trump’s presidential running mate and one of the Democrats he attacked — Vice President Kamala Harris — is the 2024 Democratic presidential nominee, Vance’s comments have come back to haunt him in a big way. The criticism has been coming from both the left and the right. Conservative GOP activist Meghan McCain, in a J…