Struggling with a decades-long decline in membership, America's labor unions desperately needed a Big Win to turn the tide and to demonstrate they are relevant. In this climate, the UFCW set its sights on Smithfield as the ultimate corporate dragon to slay and thus restore the union to its former glory.

The suits at Smithfield, meanwhile, dreaded a potential replay of the crippling strikes at meatpacking operations in Wisconsin and Minnesota in the 1980s, one of which dragged on five months and the other two years. Plus, Smithfield was paying Tar Heel workers considerably less than the company paid employees in unionized plants in other states, Waltz writes.

The North Carolina drama played out between 1993 and 2008, dating from the UFCW's first complaint to the National Labor Relations Board and ending with the third and final unionization vote, which finally succeeded in unionizing the 5,000-employee slaughterhouse. The narrow victory came five years before China's WH Group purchased Smithfield Foods in 2013 in a $4.7 billion deal.

The conditions at the plant posed logistical challenges to Smithfield as well as to the UFCW. Some years the employee turnover rate was 100 percent, costing the union a year's worth of recruits. Waves of federal raids nabbed undocumented immigrants, costing Smithfield dearly in lost productivity. In one of the rare instances where Waltz disagrees with the union's interpretation of events, she concludes that Smithfield was not colluding with immigration authorities, because it simply wouldn't have made any sense to lose underpaid, industrious workers.