 According to his wife, Merriman was convinced that defeating the fascists in Spain and then Germany would prevent a second World War.A member of left-wing groups at the University of California and friend of Robert Oppenheimer, he was chosen to lead the volunteers in Spain.As few volunteers had any military experience, Merriman's ROTC experience meant he took over the training of the 428-man strong Lincoln Battalion and, in late January, he became battalion commander.