Donald Trump has said he would end Russia’s war in Ukraine if he returned to the White House – but any rushed deal is likely to leave Kiev much weaker and European security at even greater risk.

Another major flash point a trump card the presidency will immediately seek to influence is the escalation of the conflict between Iran and Israel.

Mr Trump came close to direct war with Tehran during his first term in office, and previous restraint could give way to direct confrontation this time around.

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Then there is the overwhelming longer-term challenge posed by China, with North Korea another growing headache, especially after Mr Trump tried but failed to woo the leader of the hermit state during his first term as commander in chief.

prior to Republican victoryhostile and friendly capitals around the world were playing out what a second Trump White House might mean for their national interests and the most pressing threats to global security.

Mr Trump’s history of unpredictability is a challenge to traditional enemies – but also to Washington’s closest allies, particularly fellow members of the NATO alliance.

The president-elect has made no secret of his frustration with the way the US has funded the security blanket protecting Europe for decades.

During his first term as president, Trump threatened to withdraw the US from the alliance – a move that will almost certainly sound the death knell. His rhetoric, however, helped encourage allies to dig deeper into their pockets and spend more on their militaries.

But the damage from years of underinvestment is deep, and the pace of recovery is too slow for European allies NATO and Canada to credibly assert themselves as a strong military force any time soon.

In terms of immediacy when it comes to global crises, the impact of Mr. Trump’s victory will be felt most acutely by Ukraine and also by Iran.

In the run-up to the election, the then-candidate repeatedly claimed he would quickly end the war in Ukraine, though without explaining how or what peace would look like.

However, to indicate where his priorities lie, he accused Ukrainian President Volodymyr Zelenskyy of being “the biggest salesman on earth” for providing tens of billions of dollars in arms and other assistance that Washington – awarded to Kiev.

However, along with Ukraine’s willingness to fight, that military aid is the biggest reason Ukraine has been able to hold out for nearly 1,000 days of of Vladimir Putin war.

Stop the flow of American weapons, and Ukrainian troops – despite their own ingenuity and the support of other allies – simply won’t have the firepower to continue resisting the onslaught.

Instead, US Vice President Kamala Harris made clear that she sees continued support for Ukraine as vital to US and Western interests as it is to Kiev’s — a much more familiar position that echoed the view of her NATO partners.

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While US support for Ukraine will undoubtedly change under the Trump administration, this is not the same as facilitating a complete surrender.

The president-elect — who has cast himself as the ultimate dealmaker and adopted a new campaign slogan, “Trump will fix this” — will not want to be held responsible for Ukraine’s total absorption into Putin’s orbit.

Putin and Iran

His relationship with the Russian president is a particularly interesting dynamic.

During his first term, he infamously said he believed Mr Putin’s denials over his own intelligence agencies when it came to claims of Russian interference in the 2016 US election.

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But with the right advice, could a returning President Trump use his connection with Mr. Putin to the West’s advantage?

At the very least, it adds a new level of unpredictability — which is perhaps the most important element when it comes to assessing the likely impact of Trump’s second term.

On Iran, in stark contrast to his approach to Russia’s war in Ukraine, Trump may advocate much greater US military support for Israel’s conflict against Tehran and its proxies — perhaps even direct involvement of US forces in attacks on Iran.

He has an even tougher stance on Tehran and its nuclear ambitions than Joe Biden’s administration.

His decision to tear up a major nuclear deal with Iran was one of his most important foreign policy acts during his four years as president.

It’s also personal, with Iran accused of hacking Trump’s campaign in recent months — an attack that will surely only heighten tensions with Iran during Trump’s second term.