Former US President and Republican presidential candidate Donald Trump dances at the end of a campaign rally in Macon, Georgia, on November 3, 2024
Former US President and Republican presidential candidate Donald Trump dances at the end of a campaign rally in Macon, Georgia, on November 3, 2024 AFP News

With the return to the White House of Donald Trump, the United States and the world are set for a major new shakeup as the nationalist president turns the page on four years of nurturing allies and confronting foes.

Trump's victory over Vice President Kamala Harris will likely have the most immediate reverberations in Ukraine, where the Republican has mused about quickly ending the war by forcing concessions by Kyiv to the Russian invaders.

Trump is expected also to offer robust support to Israel, as he did during his first term from 2017 to 2021, and unleash major new pressure on Iran's clerical state.

After Trump's first term, outgoing President Joe Biden put a priority on restoring historic US relationships, which again could see tumult as Trump accuses allies of freeloading off the US military and renews questions about NATO, a bedrock of US foreign policy since the Cold War.

On the campaign trail, Trump has raged against China, with both he and Vice President-elect J.D. Vance casting the Asian power as an enemy.

Trump, however, has also insisted that he has a strong relationship with Chinese President Xi Jinping -- a sort of emphasis on personal diplomacy not entirely different than Biden.

Trump's personal style could see more fireworks in Latin America, where key US partners Brazil and Colombia and now Mexico are led by leftists.

One of Trump's key campaign promises -- the mass deportation of millions of undocumented immigrants -- could threaten havoc in the region if carried out, although Trump managed a stable, transactional relationship with Mexico's leader in his first term.

Trump is not known to have an interest in Africa and is unlikely to push for renewal next year of the African Growth and Opportunity Act, a key trade pact and priority for the continent, although Republican lawmakers support reauthorization.

Trump has broken sharply with the post-World War II consensus of the two major parties on building military and diplomatic alliances around the world, pursuing an "America First" platform of promoting US primacy above all, especially on trade.

Brian Finucane, a former State Department official now at the International Crisis Group, said Trump could be emboldened compared with his last term.

"A Trump 2.0 would be very different. He would not have any of those figures who did in fact restrain Trump at some point and in some fashion including at the Pentagon," Finucane said.

Trump has already raised fears in Taiwan by publicly questioning whether to defend the self-governing democracy, which Beijing claims and has not ruled out seizing by force.

Biden, by contrast, went further than previous US presidents by explicitly saying he would send US troops to defend Taiwan.

In the Middle East, Trump has reportedly told Prime Minister Benjamin Netanyahu to enjoy free rein in the war in Gaza for the two months until Trump takes office. In his first term, Trump fulfilled a wish-list for Israel including moving the US embassy from Tel Aviv to Jerusalem.

Further pleasing Netanyahu, Trump has vowed maximum pressure on Israel's adversary Iran, with some of his aides in the previous term stopping just short of calling for the overthrow of the clerical state.

Trump is expected to encourage more Arab states to recognize Israel, after spearheading a landmark 2020 accord in which the United Arab Emirates, Morocco and Bahrain normalized with Israel.

The Biden administration has raced to coax Saudi Arabia to normalize with Israel. But Arab states may feel more comfortable making deals with Trump, who has brushed aside concerns about human rights.

While most Western allies will shudder to deal again with Trump, his victory is welcome news for conservatives such as Hungarian Prime Minister Viktor Orban and autocratic leaders fond of Trump's transactional approach, such as Russian President Vladimir Putin and North Korean leader Kim Jong Un.

Trump, with his knack for made-for-television pageantry, would be expected to seek a summit quickly with Putin.

But Leon Aron, a senior fellow at the American Enterprise Institute, cautioned that Trump still had institutional constraints, with Putin unlikely to budge on Ukraine and Trump potentially facing opposition by Congress and his advisers to any deal seen as a US defeat.

"I think that his initial step would be some sort of very dramatic personal diplomacy - 'Vladimir, let's talk. We could resolve this,'" Aron said. "How far would that go? It's hard to predict."