[5] He played an important role in the coup that ousted President Shehu Shagari and the Second Nigerian Republic on 31 December 1983 and brought General Muhammadu Buhari to power.

[6] Buhari confirmed Shagari's appointee Muhammadu Lawal Rafindadi as director of the National Security Organization (NSO), and dismissed Aliyu from the DMI, replacing him with Colonel Halilu Akilu.

In the lead-up, due to the influence he had acquired as DMI, Aliyu was placed under intense surveillance and in turn placed pressure on the coup leaders to act swiftly.

[2] Aliyu became National Security Advisor in January 1993, and was promoted to Chief of Army Staff when Babangida passed control to the short-lived civilian government of the Nigerian Third Republic in August 1993.

[11] On 8 March 2010, Acting President Goodluck Jonathan announced that he was removing Major-General Sarki Mukhtar as National Security Adviser and replacing him with Aliyu.

[13] Speaking at a seminar in April 2010, Aliyu said the legal system seemed to promote crime and the law enforcement agencies appeared overwhelmed.

Aliyu founded the Gusau Institute in Kaduna, donating his private library and publications, to the research centre to promote national development.