Facing mounting political and economic pressure, and failing health, Sudan’s president, Omar Hassan al-Bashir, has reconstituted the janjaweed militias as his personal army. Reincarnated as the Rapid Support Forces, or R.S.F., the janjaweed fighters are being used by Mr. Bashir to consolidate his grip on power and counter the waning loyalty of the conventional army, the Sudanese Armed Forces.

It was 10 years ago this month that the United Nations Security Council demanded that Mr. Bashir disarm the militia force — notorious for the atrocities it committed during the government’s counterinsurgency campaign in the western region of Darfur — and bring its leaders to justice. The president’s response to the call to disband the janjaweed was to incorporate its fighters into the Central Reserve Police and the Border Guards. In the decade since, Mr. Bashir has been indicted on charges of war crimes by the International Criminal Court, and violence has spread across Sudan’s border with South Sudan, which became an independent state in 2011. The government is now fighting both rebels and civilians in Darfur, and in the Sudanese states of South Kordofan and Blue Nile — with no military solution in sight.

In the face of these open-ended conflicts with rebels on Sudan’s periphery, the army’s allegiance has been in decline since at least 2008. Those in the highest ranks remain loyal to Mr. Bashir. They are from the same elite, and benefit from the privileges conferred on the president’s inner circle. Their fate is tied to his.

Junior officers, however, are disillusioned. The counterinsurgency campaigns against the various rebel groups are deeply unpopular: Foot soldiers from the restive regions they are deployed to quell are reluctant to fight against their own people, while mid-ranking officers have petitioned the government to seek political solutions. Dismayed at corruption in the senior command, these officers have even called for the removal of the defense minister, Gen. Abdel Rahim Muhammad Hussein, a Bashir loyalist and fellow fugitive from the I.C.C.