In late July last year, a car packed with explosives hurtled toward the convoy of presidential candidate Muhammadu Buhari as he passed through a crowded market in the northern Nigerian city of Kaduna. The attack, which killed 50 people and was blamed on the radical Muslim terror group Boko Haram, became one of the defining moments of Buhari's election campaign, and one that he used to underline his vow to rid Nigeria of the extremist group.   

But now, after defeating president Goodluck Jonathan, Buhari, a former general who was Nigeria's military dictator nearly 30 years ago, must make good on his promise -- with an army that has so far been woefully unable to face up to Boko Haram -- and has delegated the job to the militaries of other nations. Widespread corruption in government, which Buhari has promised to fight ruthlessly, is undermining the army's ability to go after Boko Haram.  

“Tackling corruption in the military is a good place to start,” said Richard Downie, deputy director of the Africa Program at the Center for Strategic and International Studies in Washington. “Buhari must ensure that the resources that go in are being spent in a more useful way because Nigeria is a rich country that is not short of cash.”

Nigeria's security forces have been fighting Boko Haram, which has taken over a large swath of the country's northeast, for months, with little success. To fix that, Buhari -- who will be inaugurated in two months -- may have to talk to Washington first to try and fix the military relationship with the U.S., which frayed under outgoing President Jonathan.  

Last December, Jonathan canceled U.S. Army training for the Nigerian army, which was intended to make troops more capable of fighting the terrorists, because the White House had refused to green-light the sale of American-made combat helicopters from Israel to Nigeria. Washington feared that the Nigerian military would not be able to use the advanced attack aircraft in a manner that would avoid civilian casualties. 

Buhari could start anew the relationship between the U.S. and Nigeria, which has “been through a very rocky phase over the last few months,” Downie said. “It shouldn’t be too hard to get that training going again."

A Defense Department spokesman said it was too early to speculate on what relationship with the Pentagon Buhari would have. 

In the meantime, Nigeria turned to South African mercenaries, who came with their own helicopters and armored personnel carriers. One Western diplomat told the New York Times that the South Africans were playing “a major operational role” in the war against Boko Haram. Equipped with night-vision goggles, the mercenaries “are whacking them in the evening hours,” the diplomat said.

“The next morning, the Nigerian army rolls in and claims success,” the diplomat added. 

In his first public address since the election, Buhari said on Wednesday that his government would "spare no effort" in defeating Boko Haram, which has expanded dramatically in the past 18 months and killed thousands of civilians in the swath of territory it controls. "Boko Haram will soon know the strength of our collective will and commitment to rid this nation of terror and bring back peace," Buhari said. "In tackling the insurgency, we have a tough and urgent job to do."

To do that he must first whip into shape an army that, while numerically the biggest in western Africa, with 130,000 active-duty soldiers, is suffering badly from lack of resources and morale and has been largely absent from the fighting in the northeast of Nigeria. As well as mercenaries, who operate under the radar, the militaries of other countries are doing the bulk of the work against Boko Haram, entering Nigerian territory with the government's permission. Soldiers from Chad and Niger, who operate freely in the region, have been scoring numerous victories as they take back territory for Nigeria that was previously ruled by Boko Haram. In essence, they are doing what a government with Africa’s biggest economy and largest population has failed to do so far.

Buhari, the former military dictator who ruled Nigeria for 18 months between 1983 and 1985 -- he was ousted in a coup after taking power in one -- may have the credibility to help push the army into fighting more effectively as a former general with a reputation for toughness.

But winning the fight will take more than military prowess or combat helicopters. "If we’re talking about sustainable solutions to this problem,” Downie said, “you’re going to need the military at the forefront of this in the short term, but long term there will need to be more emphasis on the hearts and minds stuff, more police, more engagement with the community in the northeast, which for very good reason has felt alienated from the federal government in years gone by.”

Nigeria’s national security adviser’s officer has in fact, more than a year ago, made suggestions about how to tackle the insurgency and relieve the region's financial troubles. Among the ideas are tackling economic deprivation, increasing educational opportunities for children and reforming people who have been involved with Boko Haram. President Jonathan did not listen. 

“These suggested opportunities are all ideas that were announced, and they have not really ever gone beyond the rhetoric," Downie said. “I think Buhari should be focusing on those in the coming months and years.”

But Buhari’s tough-guy approach during his previous rule hasn't been based on winning hearts and minds. Quite the opposite. When he came to power in 1983,  he rapidly made a name for himself as Nigeria’s harshest-ever leader, known to publicly execute drug dealers, arrest corrupt businessmen and politicians by the hundreds, jail journalists and expel immigrants by the thousands.

His supporters say that he is a changed man, intent on upholding democracy. But for those who voted for him, the Buhari of old clearly has mass appeal. Many Nigerians, African affairs analyst Ayo Johnson said on CNN, feel "that they need a military leader to address fundamental problems such as terrorism."