Khalid's career was abruptly cut off on July 29, 1978, when the barrister and senior figure in Sudan's politics and diplomatic service under president Ja‘far Muhammad an-Numayri was pushed off the political stage. On that very same day, Numayri appointed Hasan ‘Abdallah at-Turabi, a militant Islamist activist who previously had led the opposition, to an influential, senior position in Khartoum's political system. Numayri, who at this point had ruled Sudan for almost a decade, took the step to strengthen his grip on power, in hopes of enticing opposition leaders to join the regime's political establishment.
Khalid moved to Washington, working at the Smithsonian Institution where he wrote his books Nimeiri and the Revolution of Dis-May  and The Government They Deserve: The Role of the Elite in Sudan's Political Evolution. Like these earlier books, War and Peace in Sudan amounts to a charge sheet against Khartoum's political ruling elite. Khalid's command of Sudanese politics and his clear point of view make it a key document for anyone wishing to understand the Sudanese tragedy.
The author focuses his criticism on Turabi, who ruled Sudan jointly with president ‘Umar Hasan Ahmad al-Bashir in 1989-99. He accuses Turabi of mobilizing Sudan's resources for funding the country's decades-old war, paying an immense price to perpetuate the dominance of Arab-Muslim rule over the largely African, Christian, and animist southern population. Khalid unequivocally blames Turabi for cutting off a political dialogue in the late 1980s between the conflicting sides—a dialogue in which Khalid himself was actively involved, alongside the Sudanese People's Liberation Army/Movement (SPLA/M). Khalid sums up Turabi's era in power as a period of "damnation."
 London: Kegan Paul International, 1985.
 London: Kegan Paul International, 1990.