Gen. Aleu began his public service as the Commissioner of Tonj South County, Warrap State, in 2012, before serving as Deputy Governor of Warrap State from 2012 to August 2015.

He briefly held the position of caretaker Governor of Warrap State from August to December 2015.

Following the creation of 28 states by President Salva Kiir in October 2015, Aleu became the first Governor of the newly established Tonj State.

His leadership experience also includes stints as Governor of Warrap State and holding ministerial roles within the state government.

In early 2018, Aleu served as Minister of Cabinet Affairs in Warrap State, playing a critical role in regional decision-making.

In April 2024, he was appointed Undersecretary for Veteran Affairs at the Ministry of Defense and Veteran Affairs.

On October 2, 2024, in a presidential decree read on South Sudan Broadcasting Corporation (SSBC), President Kiir appointed Aleu as the Director General of the National Security Service’s (NSS) Internal Bureau.

This followed a reshuffle in which Hon. Kuol Muor Muor was removed as Governor of Warrap State and reassigned to the NSS.

In a separate decree, Kiir relieved Aleu from his position as Undersecretary for Veteran Affairs and reinstated him with a promotion to Lieutenant General in the NSS, appointing him as the new NSS chief.

This move came after the removal of Lt. Gen. Akol Akoor, who was then appointed Governor of Warrap State.