"He's normalized things that were taboo. If any other Western leader acted like Trump, they'd be marginalized," said Nanjala Nyabola, a political analyst based in Nairobi. "As leader of one of the most powerful nation on earth, he's been able to behave with complete disregard for the institutions and norms that rely on good faith and trust in the international community. Undercutting that will be Trump's lasting legacy."
"When the President of the United States congratulates authoritarians for winning unfair elections or calls genuine dictators his friend, it gives those leaders the propaganda win of an endorsement from the supposed moral leader of the world," says Nic Cheeseman, professor of democracy at the University of Birmingham. "When you combine these endorsements with Trump's reduced presence on the world stage, he has created space for strongman to behave even more aggressively at home and internationally."
Over the past four years, Trump has also withdrawn from international agreements and questioned the relevance of international institutions that have historically relied on America's political and financial support.
His actions have the direct and immediate impact of reducing the effectiveness of multilateralism. "When Trump pulls out of the World Health Organization in the middle of a pandemic and accuses it of working with China, he risks destroying the long-term credibility of international bodies in dealing with global crises," says Cheeseman. "When he pulls out of treaties like the Paris climate accord, he reduces the international community's ability to ask a country to stop chopping down trees. If the US is no longer a stakeholder, why should anyone else be?"
Nyabola thinks that the long-term impact of Trump's unilateralism carries two significant risks. First, his criticisms of institutions like NATO and the UN could "unravel decades of work that went into creating forums built on trust and honestly." Second, she believes that his unrestrained style of leadership has "changed international expectations of the office of president." Those expectations might include standing beside democratic nations when their independence is threated, or protecting Western security interests and promoting stability, rather than befriending and congratulating hostile actors who seek to undermine these principles.
This creates a problem for those who succeed Trump -- either now or in four years -- who would like to present his presidency as an aberration. "His rhetoric and behavior have changed what friends and enemies can claim to expect from a US president," says Jennifer Cassidy, a diplomatic scholar at Oxford University. "This means a country like Iran now has a free pass to say they will never negotiate with the US again. What is the point, they can credibly claim, if someone like Trump comes along again and rips it all up?"
Trump's transformation of America's global standing will cast a shadow over whoever eventually replaces him as president. If that's Joe Biden this January, it's likely he will try and restore some of America's international relations from day one. The difficulty he faces is, no matter how loudly he champions returning to normal, Trump happened once and the rest of the world is aware he could happen again. "Trump 2.0 could be a younger, more intellectually coherent prospect. They could have a more overt desire to tear apart the post-war world order," says Cheeseman.
No matter how much those who revered the American-led world order might want a new administration to flick a switch which undoes the past four years, it's going to take time for the US to be fully trusted by allies again. And while it rebuilds that trust, those who oppose Western democracy will continue to occupy the space that Trump afforded them when he vacated his post as leader of the free world.