Donald Trump says he would end Russia’s war in Ukraine should he return to the White House – but any rushed deal will likely leave Kyiv much weaker and European security in even greater peril.

Another major flashpoint a Trump presidency would immediately seek to influence is the escalating conflict between Iran and Israel.

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

US election latest: Harris and Trump make final pitches

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 stint as commander-in-chief.

With the US election on a knife edge, hostile and friendly capitals around the world have been gaming what a second Trump White House might mean for their respective national interests and for the most pressing global security threats.

Mr Trump’s track record of unpredictability is a challenge for traditional foes – but also for Washington’s closest allies, in particular fellow members of the NATO alliance.

The Republican nominee has made no secret of his frustration at how the US has for decades bankrolled the security blanket that protects Europe.

During his first term as president, Mr Trump threatened to withdraw the US from the alliance – a move that would almost certainly sound its death knell. His rhetoric did help to spur allies to dig deeper into their pockets and spend more on their militaries, though.

But the damage of years of underinvestment is deep and the pace of recovery is too slow for European NATO allies and Canada to credibly stand on their own as a potent military force any time soon.

In terms of immediacy when it comes to global crises, the impact of a Trump victory on 5 November would be felt most acutely by Ukraine and also by Iran.

The presidential candidate has repeatedly claimed that he would quickly end the Ukraine war, though without explaining how or what peace would look like.

In an indication of where his priorities lie, however, he has accused Ukrainian President Volodymyr Zelenskyy of being the “greatest salesman on earth” for securing tens of billions of dollars in weapons and other assistance that Washington has given to Kyiv.

Yet – coupled with Ukraine’s willingness to fight – that military aid is the biggest reason why Ukraine has managed to withstand almost 1,000 days of Vladimir Putin’s war.

Stop the flow of American weapons, and Ukrainian troops – despite their own ingenuity and the support of other allies – will simply lack the firepower to keep resisting the onslaught.

By contrast, US vice president Kamala Harris, who is vying for the top job, has made clear that she views continued support to Ukraine as being as vital to US and Western interests as it is to Kyiv’s – a far more familiar stance that echoes the view of her NATO partners.

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

The former president – who portrays himself as the ultimate dealmaker and has adopted a new election slogan – “Trump will fix it” – will not want to be held responsible for the total absorption of Ukraine into Mr Putin’s orbit.

Putin and Iran

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

When president, he infamously said he trusted Mr Putin’s denials over his own intelligence agencies when it came to claims about Russian interference in the 2016 US election.

But with the right advice, might a future President Trump be able to 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 potential impact on the world of a second Trump term.

On Iran, in stark contrast to his approach to Russia’s war in Ukraine, a future President Trump may well back much greater US military support for Israel’s conflict against Tehran and its proxies – perhaps even direct involvement by US forces in strikes on Iran.

Mr Trump has an even tougher stance towards Tehran and its nuclear ambitions than Joe Biden’s administration.

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

It is also personal, with Iran accused of hacking the Trump campaign in recent months – an attack that would surely only heighten tensions with Iran during any second Trump term.

On election night, Sky News will have access to the most comprehensive exit poll and vote-counting results from every state, county and demographic across America through its US-partner network NBC.

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A red alert warning of “extreme danger” because of torrential rain has been issued for Barcelona, as elsewhere in Spain search teams continue to scour flooded areas for bodies.

At least 217 people have died after heavy rain in eastern Spain caused flash floods that swept away almost everything in their path.

People were trapped in cars, homes and businesses as the waters surged through the disaster zone last week.

Six days later, the search and rescue operation continues for the unknown number of missing people, with thousands of soldiers brought in to help.

And as communities continue to reel from the catastrophic floods – and mourn their losses – more rain is forecast for parts of the country.

Today, the local government in Catalonia has warned of “continuous and torrential” rain in two regions, saying people should avoid travel and stay away from streams and ravines.

A red alert “extreme danger” warning has been issued for Barcelona.

“Do not travel unless strictly necessary,” the alert told people nearby.

Footage on social media shows heavy rainfall overwhelming stairwells and leaving streets strewn with water.

Dozens of flights have been cancelled at El Prat airport after the terminal building was flooded.

Elsewhere in eastern Spain, much attention has been paid to an underground car park in Aldaia, where emergency services have been trying to drain the floodwater to gain access.

There had been fears that dozens of bodies could be found inside the car park after people died trapped by the rising waters at the Bonaire shopping centre.

However firefighters on the ground have downplayed the situation, Spanish media report.

“Since yesterday afternoon we were able to get in with canoes, boats, drones and on foot,” one of the firefighters told El Pais.

“Yesterday we went through the entire car park and luckily we haven’t found any bodies.”

They said that could change as the car park empties, but that at the moment the cars are all empty.

Read more:
Flood-hit Spanish towns desperate for leadership
Spain mounts biggest peacetime disaster recovery

There has been anger at the response from authorities and a group of survivors hurled mud and insults at Spain’s King Felipe when the monarch visited one of the worst-affected towns.

By the time authorities sent alerts to mobile phones warning of the seriousness of the flooding and asking people to stay at home, many were already on the road or in places like underground garages that became death traps.

Valencia’s MotoGP race, which had been scheduled for later this month, has been cancelled after floods wrought destruction on the track.

Thousands of volunteers have been helping to clear away thick layers of mud from streets and homes.

The story of these floods has been full of grim, unsettling images.

Now there is another one – the Bonaire shopping centre in Aldaia.

Today, it was an awful place. Not because of the immense damage wrought by the floods, but because of the horror that may lie ahead.

The emergency services are pumping out the underground car park that lies beneath this retail complex, one of the biggest in the country, and they don’t know what they will find.

There will be bodies – that seems sure. The question is how many. And the fear is that it could be dozens.

You can see the ramps that run down to the car park, and you can also see the water level glistening, not far down the ramp.

Pumping out this entire car park will be a marathon job. Searching it will take patience, specialist equipment and stoicism. There will surely be grim discoveries down there.

Scuba diving teams have been sent in, but we were told that they have been unable to go into the water so far. It is full of debris, oil, diesel, and goodness knows what else.

Today we saw an array of equipment being delivered – boats, pumps, a military ambulance, kayaks and lifting machinery.

An enormous amount of resource is being thrown at this, at a time when so many towns are complaining that they feel forgotten.

Cristina Vano, a judicial expert, is working here as a volunteer, checking the cars strewn around in the ground-level car parks.

Her job is to peer inside and see if she can see a body. If she can’t, she puts an X on the side using coloured tape; if she can, she calls the police.

Read more:
Flood survivors hurl mud and insults at King of Spain
Anger at response to Spain floods grows
‘Living with corpses at home’: Spain reels from flash floods

She is waiting for the first vehicles to be pulled from the Bonaire underground car park, and she is steeled for it to be a horrible experience.

“There is space for 1,700 cars in there,” she says.

“We were told it wasn’t full, but there were certainly many cars in there. The problem is that a lot of people took refuge there, so we don’t know what to expect.

“The police in Aldaia were talking about us finding maybe 80 people – I hope it will be less. It’s really sad, but we are expecting a lot.”

We speak to the police, who tell us that searching the car park will be a long and complicated process.

They don’t want to make any estimates about the number of cars involved, nor the number of people. But someone involved in the operation speaks to us after coming out.

“A lot more than a hundred cars are in there,” the person says. “Maybe hundreds.”

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There is an army officer, from special services, who tells me that his unit of Green Berets are ready to do anything that is needed. They have been helping to clear out the shopping centre for days now, and will continue. But he knows this is not a quick job.

On the far side, we see a group of firefighters walking slowly away from that cursed ramp that leads down to the car park. Their faces are drawn, an expression that we see a lot during a day observing this recovery mission.

Everyone involved in this knows that there is no chance of finding a survivor in this flooded car park. All they can do is hope that it’s not as bad as they fear.