Trump's objectively regarded as the most comparatively peaceful US president in decades since he didn't start a new war like his predecessors did despite continuing their policy of assassinations, Color Revolutions, and other unconventional acts of aggression like his infamous trade war with China. Less people across the world were killed by his country than at any time since former President Jimmy Carter, but that doesn't mean that Trump's international legacy is a rosy one. To the contrary, while less people directly suffered during his rule, the world is arguably much less safe than it's been in decades as a result of him pulling the US out of different international organizations and especially arms control pacts.
Russian Foreign Ministry spokesman Maria Zakharova rightly described this as the US having “gone haywire with the idea of its own exceptionalism” to the dangerous point where its population now “thinks that they don’t owe anybody anything, that they should not obey anyone, not even the law or international rights”. Although Biden might reverse some of this, the damage is already done, she believes. It was one thing for Trump to pull the US out of the Paris Agreement and World Health Organization among others, which didn't really change anything across the world for the worse (at least in the short term), and another entirely for him to rubbish the Intermediate-Range Nuclear Forces (INF) Treaty and risk letting the New START lapse next month.
Furthermore, although not mentioned in her remarks, Trump also oversaw the US' most intense sanctions regime against Russia in history which was predicated on entirely fabricated pretexts related to the officially debunked accusations that Moscow helped the 45th president get elected. Trump's far from “Putin's puppet” like his opponents dishonestly claimed and is more akin to his worst enemy ever after all that he did to actively “contain” the Eurasian Great Power. This forced Russia to defensively react, which in turn was deceptively misportrayed by the US' permanent military, intelligence, and diplomatic bureaucracies (“deep state”) as “acts of aggression” that were then exploited to “justify” more intense “containment” measures.
Global strategic stability has been harmed like never before after Trump pulled out of the INF Treaty, the Open Skies Treaty, and might let the New START lapse next month without agreeing to Russia's proposed one-year minimum emergency extension. The amount of people who could suffer in the long term might surpass that which directly suffered under his predecessors in the worst-case scenario, especially if Trump's risky plan for the dual “containment” of Russia and China in the Arctic triggers a war by miscalculation. In other words, while Trump was the most comparatively peaceful US president in recent memory, that might all just be an illusion since he really destabilized the world in a tremendous way but the consequences aren't immediately visible.
His unleashing of unrestrained American Exceptionalism will certainly be exploited by Biden and his team of liberal-globalist ideologues, who'll feel emboldened by the precedent that he set to carry out more regime change wars abroad under the pretext of “spreading democracy” and “defending human rights”. Ironically, just like Obama -- one of the most internationally disastrous US presidents in recent memory -- paved the way for one of the most peaceful, so too might Trump have paved the way for the Obama 2.0 of the Biden Administration. Trump never tired of blaming Obama for creating such a mess across the world, but when Biden makes everything much worse, observers can't help but blame Trump for making it all possible.