It is difficult to try to predict the decisions that US President-elect Donald Trump will make when he returns to the White House.

But one thing seems unlikely to change: his dislike of patient, principled diplomacy as a means to peace and his preference for transactional politics and populist gestures.

This brings openings and perils in some areas in Africa.

Eight years ago, the Obama administration was working with the African Union (AU) to change United Nations (UN) rules for funding peacekeepers to put African missions on a firm financial basis.

The AU Commission worked with the UN and other multilateral organisations to construct an “African peace and security architecture” that ranged from proactive diplomacy to avert looming conflicts through to coordinated mediation efforts and peacekeeping operations, all underpinned by norms and principles enshrined in the UN Charter and the AU Constitutive Act.

How long ago that seems.

Plans for more robust peacekeeping evaporated in the transition to the first Trump administration.

Since then, no new UN or AU peacekeeping missions have been authorised. Several – including in Darfur, Sudan and Mali – have been closed, and others scaled down.

The Biden administration did not reverse the trend.

The idea of “liberal peace” – that peace, democracy, justice and open markets all go together – had long been a powerful strand in US global strategy.

The AU embraced its multilateralism but recoiled from being lectured on human rights and democracy and were divided on Western military interventions such as in Libya.

Some African leaders preferred Trump’s candour and focus on results.

The “Trump Doctrine” for the Middle East and Africa swept aside multilateralism in favour of transactional deals with American allies in Egypt, Morocco, Saudi Arabia, the United Arab Emirates (UAE) and, above all, Israel.

Prime Minister Benjamin Netanyahu and UAE President Mohamed bin Zayed set the strategy of the Abraham Accords, and Trump basked in the glory when Arab countries signed up.

Trump’s other consistent positions were hostility towards China’s influence on the continent and aversion to deploying American soldiers.

At the request of Egypt’s President Abdul Fattah al-Sisi – described by Trump as “my favourite dictator” – then-Treasury Secretary Steven Mnuchin took charge of mediating Egypt’s dispute with Ethiopia over the Nile waters.

The immediate issue was how much water would be retained by the Grand Ethiopian Renaissance Dam as it approached completion.

As the talks faltered, Washington put its thumb on the scales, suspending aid to Ethiopia, while Trump suggested that Egypt might “blow up” the dam.

America recognised Morocco’s claim over Western Sahara in exchange for Rabat signing the Abraham Accords and thereby recognising Israel.

In the era of “liberal peace”, an agreement to end a civil war was the drafting of a democratic constitution, along with measures for disarming and demobilising rival armies, transitional justice and reconciliation, and aid-funded programmes to deliver a peace dividend for the afflicted populace.

The first Trump administration preferred direct deal-making, whereby autocrats cut a private bargain over the counter. Scholars call this the “illiberal peace”.

• Trade, aid, security: What does Trump’s win mean for Africa?

When then-Secretary of State Mike Pompeo visited Sudan after the popular revolution that led to the ousting of military-Islamist ruler Omar al-Bashir, his main agenda was a simple trade: America would lift sanctions when Sudan agreed to sign the Abraham Accords.

In October 2020, the White House announced that President Trump had “brokered a historic peace agreement” between Israel and Sudan.

On the heels of deals with Bahrain and the UAE, and weeks before Americans voted in the presidential election, this was Trump’s “October surprise”.

It came too late to save Sudan from the economic crisis that crushed its democratic experiment and fell away after Trump lost to Joe Biden.

But it’s fair to assume that the second Trump administration will continue this way.

The exact alignments and deals are impossible to predict, and much will depend on the individuals appointed to key positions. But the “liberal peace” is now dead and buried.

Sudan is currently Africa’s largest war and its biggest famine for decades. There is no sign that Trump is concerned.

The biggest obstacle to peace is that the UAE supports one side with weapons and cash while Egypt and Saudi Arabia back the other. There is no prospect for peace while this continues.

For those Arab powerbrokers, Sudan is just one element in their geostrategic calculations, ranked below Israel-Palestine, Iran and relations with Washington.

But if there is a reshuffle of the Middle Eastern political cards, a bargain over Sudan might be a by-product, even an opportunity for Trump to bask in the glow of an unexpected peacemaker.

It will not bring an end to violence, let alone usher in democracy, but it would open the space for serious negotiations.

A similar calculation holds for Ethiopia and its fractious relations with an Egypt-led coalition that includes Eritrea and Somalia.

Along with an array of African leaders, Ethiopia’s Prime Minister Abiy Ahmed is heavily reliant on Emirati largesse. Tensions in the Horn of Africa would be reduced if Egypt and the UAE align their strategies.

The Biden administration’s policy towards the Horn of Africa was neither committed to principled multilateralism, nor ready to use its leverage with the Gulf states.

Its envoys could only grasp for minor wins such as pauses in the fighting or opening checkpoints for aid convoys.

The tangled wars in Sudan, Ethiopia and their neighbours cry out for bold action – and if he were so minded, Trump might cut the Gordian Knot.

But the risks of a conflagration are high.

The Trump White House will not be likely to restrain bellicose tendencies by Middle Eastern powerbrokers or African leaders, and – especially during the US policy vacuum of the next few months – any one of those leaders could launch a war, confident that America will not respond.

In his first term, Trump showed no interest in the US military footprint in Africa.

Apparently on a whim, he ordered the withdrawal of American troops from Somalia, where they were involved in the war against the jihadist group al-Shabab – a decision reversed by the Biden administration.

It’s unlikely that Trump will pay attention to the Pentagon’s operations against jihadists there or in the West African Sahel, unless there is a high-profile incident with American casualties.

And America’s Middle Eastern allies will be keen for the US to retain its military base in Djibouti.

Reports of collusion between Yemen’s Houthis and al-Shabab, heightening risks of attacks in East Africa or on shipping in the Indian Ocean, may rekindle US interest in military operations.

Alternatively, missions could be outsourced to allies such as the UAE or private military contractors.

Kenyan President William Ruto’s rapport with Biden will do him no favours, but Kenya’s new status as a “major non-Nato ally” – and contributor of police to Haiti – will likely retain good standing within the Department of Defense.

West Africa is today the locus of the world’s most active jihadist movements as well as a tide of putschists who cut deals with Russia’s security outfit, the Wagner Group, now merged into its Africa Corps.

If Trump sees West Africa through the prism of relations with Moscow, and his planned deal with President Vladimir Putin over the war in Ukraine, it will introduce a wild card into the region’s politics.

But tensions will arise because his ally, Morocco, has its own ambitions for strategic leadership across West Africa.

It’s a major non-Nato ally and has been leery of Russian influence in Algeria, Libya and the Sahel – adding up to a mix that would be stirred if Trump cuts deals with Putin.

Transactional politics imply cutting deals with coup leaders and warlords whose crimes are their credentials.

AU principles such as outlawing unconstitutional changes in government will be disregarded.

Nigeria’s President Bola Tinubu may have preferred Biden, but he is familiar with Trump’s style of politics and will seek a formula for keeping America onside in its war against jihadist group Boko Haram.

In February, just weeks after the presidential inauguration in Washington, Africa’s leaders will meet in Addis Ababa, Ethiopia, to elect a new chairperson of the AU Commission.

The outgoing chairperson, Chad’s former Prime Minister Moussa Faki Mahamat, was content to be a trader in the political bazaar of the Trump-Biden years.

His successor will face the challenge that Africa’s best formula for peace and security lies in norm-based multilateral cooperation, but 2025 will be an inauspicious year for reviving that project.

Alex de Waal is the executive director of the World Peace Foundation at the Fletcher School of Law and Diplomacy at Tufts University in the US.

• EXPLAINER: When does Trump become president again?

• POLICIES: Seven things Trump wants to do

• GLOBAL: What Trump’s win means for Ukraine, Middle East and China

• ANALYSIS: Will Trump’s victory spark a global trade war?

• IN FULL: All our election coverage in one place

North America correspondent Anthony Zurcher makes sense of the race for the White House in his twice-weekly US Election Unspun newsletter. Readers in the UK can sign up here. Those outside the UK can sign up here.

Go to BBCAfrica.com for more news from the African continent.

Follow us on Twitter @BBCAfrica, on Facebook at BBC Africa or on Instagram at bbcafrica