The replacement mechanism first-wave mill girls faced became the defining response of American capitalism to organized labor: replacement. They could organize because the Industrial Revolution hadn't fully eradicated their independence; they had farms to return to and enough solidarity to build the first permanent female labor union in American history, but were replaced by a new workforce, one unable to resist. The mills moved south; southern workers organized and the mills moved to Mexico. Then China, then Bangladesh, then Vietnam. Each move followed the same logic that the Boston Associates discovered in 1845: the most effective reform is a new, more desperate workforce.