As US president, Donald Trump has specialised in bullying and berating allies. By contrast, Joe Biden has promised that he will treat US allies with respect and consideration. This is more than a matter of common courtesy. Allies are a crucial American asset in pushing back against unwelcome behaviour by China, Russia and other potential adversaries.

Fortunately, the new president is pushing at an open door. After four years of Mr Trump, America’s allies in both Europe and Asia are eager to embrace a new era of co-operation with the US. The EU has already taken the striking step of setting out its own agenda for transatlantic co-operation, even before Mr Biden has been sworn in. The priorities identified by the Europeans look like the basis for a new era of engagement. They include global health, climate change, trade, technology and security.

Each of these areas offer the possibility for productive co-operation. With the pandemic still raging, Mr Biden has promised to take the US back into the World Health Organization. If and when he does, he should accept the EU suggestion to work together on reform of the global health system. The need for an organisation such as the WHO is unarguable. But the pandemic has revealed a whole new set of urgent issues — including the strengthening of early-warning systems, and the production and distribution of vaccines.

The Biden administration’s decision to re-engage in global climate talks — combined with a UN summit, chaired by the UK, this year — provides another opportunity for Europeans and Americans to work together. Both Washington and Brussels are now talking about linking the trade and climate agendas. Unilateral action by either side would risk carbon-border taxes sparking a transatlantic trade war. But if the EU and US co-ordinate their approaches, they could help to raise global environmental standards — without giving a boost to protectionism in the process.

There are similar opportunities and risks in technology policy. There is now a strong feeling on both sides of the Atlantic that the big tech firms need much heavier regulation. But America and Europe have different approaches to privacy. US policy is also inevitably coloured by the fact that so many of the world’s tech behemoths are American. Both sides, however, are increasingly conscious of the need to shape global standards — partly to deal with the security and privacy concerns raised by the rise of Chinese tech giants. Once again, discussion and co-ordination between Washington and Brussels would be in both sides’ interests.

There is also scope for a new understanding between America and Europe on the vexed issue of “burden sharing”. Donald Trump was not the first US president to complain, justifiably, about Europeans’ freeriding on American defence spending. At the same time, America has traditionally been reluctant to see the EU develop its own defence identity, for fear that any such development would undermine Nato.

There is an obvious trade-off available here. Europeans need to make credible commitments to spend more on their own defence. In return, the Biden administration could take a more relaxed attitude to these defence efforts being co-ordinated, and perhaps even partly funded, at a European level. If that development took place in full consultation with the Biden administration, it would strengthen rather than undermine Nato.

The past four years have put a huge strain on the transatlantic alliance. The next four provide an opportunity to breathe new life into the partnership between the US and Europe.