Third of a four-part. Timewatch eassessment of the life and work of former US president Lyndon B Johnson. We Shall Overcome. Johnson had galvanised America with his appeal for racial justice and his vision for a 'Great Society'. But at the same time, he had promised not to send American troops to Vietnam. Political experts and those who knew him best explain why, without national debate or congressional approval, he expanded a war he had never understood. Johnson's vision for America was about to be overtaken by a full-scale land war in Asia.