Agriculture. Agriculture became the dominant industry of the American Great Plains and Canadian Prairies during the second half of the nineteenth century and the early decades of the twentieth century. Farming operations had, of course, been carried on in some parts of the Plains for many years.
Explanation: I see your point. Evan though Nazi war criminals are probably old and can't do much, that wont stop them from contacting younger people and paying them to continue the Nazi work. Hope I helped!!!!!