Donald Trump has picked Ohio senator J.D. Vance as his running mate, choosing a grassroots favorite ahead of more seasoned political operators. The former president left it until the last possible moment, using all his showman skills to leave the world guessing, before opting for 39-year-old Vance after the Republican National Convention had already begun in Milwaukee, Wisconsin. Vance swept to national attention when he published his bestselling memoir 'Hillbilly Elegy,' in 2016, the year Trump was elected president. He has been a senator for less than two years but has established himself as one of the fiercest defenders of...