When Joe Biden and Donald Trump sat down for their fireside chat last week, the outgoing president made it clear that supporting Ukraine was in the United States’ interest.
Allowing Vladimir Putin and a resurgent Russia to succeed on the battlefield would ultimately risk Washington being dragged into a much wider European ground war, Mr Biden told his former presidential rival.
It is an argument Mr Trump has swatted away throughout his latest election campaign.
But as he prepares for a return to the White House under the promise to end the war on day one, there are reasons why he may now be listening.
Mr Trump has promised to strike a deal between Putin and Volodymyr Zelensky to bring fighting to an end. And he knows a thing or two about negotiating from a position of strength.
Almost a week on from that fireside chat and Mr Biden has now moved to further arm Ukraine by lifting a ban on using long-range missiles inside Russian territory.
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Many of Mr Trump’s allies, including his son, have expressed outrage at the decision, warning of World War III.
But all the people that matter in Mr Trump’s inner circle — his hawkish new secretary of state, national security adviser and defence secretary — have remained eerily quiet.
Mike Waltz, Mr Trump’s pick for national security adviser, described the decision to grant Ukraine permission to use the Atacms missile system in cross-border raids as an “escalation”, but rather than criticising the move said it was a “tactical” choice by the White House.
In an interview on Fox News, he went on to say Mr Trump was eying up a “grand strategy” to end the war.
One plan, floated by Mr Trump’s former policy advisers, suggests arming Ukraine with sufficient firepower in order to coax Putin to the negotiating table.
Mr Trump has a direct line to the Russian president and has already spoken to both him and his Ukrainian counterpart on the phone since he was elected.
Some believe Mr Trump wants a Nobel Peace Prize, something that eluded him after Barack Obama was handed the award.
Overseeing a Ukrainian capitulation might allow Washington focus on its main foreign policy objective — controlling China — but it won’t adhere him to America’s allies.
White House officials have insisted that they moved unilaterally with the missile decision, fearing Mr Trump would abandon Ukraine.
Ukraine’s position is weakening. Its forces are crippled by manpower shortages, while Russia is seizing land, slowly but steadily, across almost the entirety of the front line.
Mr Biden has flown to Brazil, where he will appeal to G20 leaders to follow his lead to strengthen Ukraine’s hand further ahead of Mr Trump taking office on Jan 20.
The White House has also been motivated by the appearance of North Korean troops on the battlefield in Ukraine.
Estimates vary for the number of men from the communist nation sent to assist Russian forces.
But reports from the sidelines of the G20 meeting suggest North Korea could eventually deploy as many as 100,000 troops.
The latest figures being bandied around Washington are that 10,000 North Koreans will be involved in a 50,000-strong force used by Russia to reclaim a sliver of land in its Kursk region seized by Ukraine earlier this year.
This area of southern Russia is where Ukraine has been granted permission to use the Atacms system.
George Barros, a researcher with the US-based Institute for the Study of War, believes this is critical to the decision to allow use of the missiles.
“I think the introduction of the North Koreans and the transition to the new administration are two important catalysing factors here that probably changed the administration policy,” he said.
What part — if any — Mr Trump played at the White House transition meeting remains under wraps for now.
