Dr. Martin Luther King Jr. on the picket line at the Scripto plant in Atlanta, Ga., December, 1964. AP Peter Cole, Western Illinois University If Martin Luther King Jr. still lived, he’d probably tell people to join unions. King understood racial equality was inextricably linked to economics. He asked, “What good does it do to be able to eat at a lunch counter if you can’t buy a hamburger?” Those disadvantages have persisted.