Joe Biden has promised to put an end to Donald Trump's isolationist, disruptive approach to global relations.
But a Biden administration bid to restore American leadership will require time and political capital at a time when the superpower's global role stands in doubt at home and abroad.
While diplomats are not likely to hear the phrase "America First" for a while, Biden will face challenges including countering China, re-entering the nuclear deal with Iran, resetting relations with Europe and dealing with the fallout of Brexit on the relationship with the UK.
What Biden wants: Keen to rebuild the European alliances that Trump has repeatedly snubbed, Biden is likely to be the most Atlanticist US president in a generation. He prides himself on his Irish heritage and will move away from Trump's overt hostility to the EU. Biden will also be a strong backer of the Nato military alliance.
The president-elect is opposed to Brexit, though has accepted it as a fait accompli. However he will find it easier to work with the UK if it can avoid a no-deal divorce from Europe that respects Irish border agreements.
Biden has also promised to harden the US line on Russia and "impose real costs" on the country for violations of international norms. His support for a strong Nato is explicitly aimed at countering Russian aggression, and he has vowed to stand with Russian civil society against what he calls president Vladimir Putin's "kleptocratic authoritarian system". However he will have to quickly open negotiations with Moscow to extend the New START nuclear arms reduction treaty before it expires on February 5.
What they want: While many European officials accepted that Trump was a blunt messenger for structural change — including more defence spending from Nato allies and a withdrawal of US troops from Germany, they still see the US military might that underpins Nato as essential to Europe's security. They would also like Washington to engage more in dealing with regional crises from Belarus to the Eastern Mediterranean.
Upshot: Expect 18 months of happy hand-holding events that put the postwar alliance system back at the heart of US relations with the rest of the world, starting with efforts to lead a global response to coronavirus. But the crunch could come over China, Brexit and trade.
What Biden wants: The US president-elect has promised to rejoin the Iran nuclear deal Trump withdrew from, if Tehran comes back into compliance with the multilateral accord designed to curb its atomic ambitions. He has also vowed to reset relations with Saudi Arabia which he has called a "pariah" state.
But like Donald Trump, Biden wants to end America's forever wars and plans a shift in US loyalties in the Middle East. The Democrat will not move the US embassy from Jerusalem, where Trump relocated it from Tel Aviv in 2018. He has no plans to push for a two-state solution. Biden's top advisers have also made clear his foreign policy priorities lie elsewhere.
What they want: Iran wants compensation for its treatment at the hands of the Trump administration and all sanctions lifted as the price for its return to the nuclear deal. At present, it is still developing its missile programme.
Saudi Arabia meanwhile is concerned a Biden administration could halt arms sales and impose a renewed chill on relations.
The UAE would like to see the US take more punitive action against Turkey, and, if Biden agrees to re-enter the Iran deal, to ensure Iran's missile programme and support for militias in the region are also addressed. It also wants a seat at the negotiating table with regional powers on any Iran discussions.
Upshot: There is likely to be a timing crunch because of Iran's presidential elections in June, which could hand power to hardliners who would be more difficult to negotiate with. A new Biden administration will have to work fast to agree a new approach to Iran with the accord's European signatories — the UK, France and Germany.
What Biden wants: One Biden adviser described the president-elect's foreign policy priorities as "China. China. China. Russia". Team Biden will inherit a US foreign policy establishment that views Beijing with far more concern than it did during the Obama era. However it remains unclear what combination of co-operation, competition and confrontation Biden will use to engage with the US' rising power rival.
While he will probably refuse to endorse a new Cold War that could put America's leading global role under threat, he will seek to push back on conventions governing technology and investment. He will also maintain a robust US military presence on China's doorstep.
Biden will seek to strengthen co-ordination with European partners on investment screening, intelligence sharing and emerging technologies in a bid "to get on the same page with our allies regarding China," a Biden official said.
He will also try to strengthen regional partnerships with allies given short shrift under the Trump administration, such as South Korea.
What they want: Some experts think China will breathe a sigh of relief with Biden at the helm. Europeans are hoping for less aggressive public rhetoric than during the Trump years, but many officials expect little let-up in private pressure by the US. The tide in Europe is also shifting to greater scepticism towards Beijing.
Upshot: Some Democrats say Biden underestimates the threat posed by China's military, economic and diplomatic ambitions. Most European officials insist they don't see themselves as equidistant between Washington and Beijing — but they are also eager to preserve economic relationships with China and the potential for partnerships in other areas such as climate change.
What Biden wants: Biden has some of the same protectionist tendencies as Trump. He proposes making federal agencies procure only US services and goods, and has floated a tax to penalise US companies for moving jobs and manufacturing overseas. Like Trump, he has argued that the World Trade Organization needs to be reformed and better able to deal with non-market economies like China.
However, although Biden has signalled he will continue to be tough on China on the trade front, he is unlikely to replicate the confrontational tariff regime fostered by Trump. But the extent to which he will remove or lower tariffs — or apply further tariffs — is unclear.
In line with his broader foreign policy, Biden wants to lower trade tensions with Europe. But this means resolving some major disagreements, including the decades-long row over airline subsidies and the debate over how to fairly tax big tech companies.
What they want: The immediate hope for foreign democracies will be that a Biden administration will join with the consensus of other member states in backing Ngozi Okonjo-Iweala as the new director-general of the World Trade Organization. The current administration is blocking the appointment of a new leader.
Europe and the UK are also seeking progress in talks about aircraft subsidies and the end of related US tariffs on European goods including cheese, wine and olives. Those same countries will also aim to sort their disagreement with Washington over digital taxation, and will work to have tariffs on European steel and aluminium lifted.
The UK, which is leaving the EU single market in January, will try to close a trade deal with the US once Biden takes office, but the Biden campaign has said this will not be at the top of the new president's priorities.
Upshot: Substantial issues remain with Europe. Trade tensions with Beijing, too, are likely to continue. Experts expect trade wars to continue — but ones that will be waged in back rooms and not over Twitter.
What Biden wants: Biden has pledged to rejoin the Paris Agreement on Climate Change, which the US withdrew from on Wednesday. He plans to integrate climate change targets across every aspect of US foreign policy, national security and trade. He has set a target of net-zero emissions by 2050 for the US and has vowed to entirely rely on and even export clean energy.
He has also said he would lead a global effort to ensure every significant carbon-emitting country raises its own ambitions for domestic climate targets, with transparent, enforceable goals — with China particularly in mind.
What they want: EU countries need the US to come back into the international coalition to fight climate change. The UK, which is hosting COP26 in November 2021, hopes to use the UN climate summit to reduce tension over Brexit between Biden and prime minister Boris Johnson.
Upshot: China and Japan both recently laid out hefty new targets for themselves to go carbon neutral by 2060 and, in Tokyo's case, by 2050. That puts the pressure on Biden to improve America's goals and to find a bright spot in US-China relations even as Biden will seek to reclaim the leadership mantle in global climate diplomacy.
Written by: Katrina Manson, Aime Williams and Michael Peel
© Financial Times