Western leaders raced to respond to the return of Donald Trump to the White House with a powerful mandate to put his policy of “America first” into action once again. But many of the public congratulations could do little to disguise the private foreboding of what the next four years will augur for European security, populism and the world economy. Viktor Orbán, the Hungarian prime minister and the European leader closest to Trump, was one of the first to hail his ally’s victory. He posted on social media: “The biggest comeback in US political history! Congratulations to President @realDonaldTrump on his enormous win. A much-needed victory for the world!” Orbán, isolated inside the EU, is due this week to host more than 45 leaders in the European political community in Budapest, which will provide the first opportunity for European leaders to assess the implications for security, including for Ukraine’s war against Russia. Volodymyr Zelenskyy, the Ukrainian president, put a brave face on a result that could mean a sharp cut in funding for his war effort, saying Trump’s commitment to peace through strength could bring a “just peace closer”. The new Nato secretary general, Mark Rutte, said Trump’s leadership “will again be key to keeping our alliance strong. I look forward to working with him again to advance peace through strength.” Nato – and its members’ military contributions – have been frequent targets of Trump’s criticism. Benjamin Netanyahu, the Israeli prime minister and another ally of Trump, was also early to send his best wishes. “Congratulations on history’s greatest comeback! Your historic return to the White House offers a new beginning for America and a powerful recommitment to the great alliance between Israel and America,” he said on X. Netanyahu will be hoping that Trump will continue to supply US arms and also increase pressure on Iran. With Tehran expected to respond to Israel’s 25 October strikes on its territory that killed four soldiers, the deputy chief of the Islamic Revolutionary Guards Corps, Ali Favadi, said: “The Zionists do not have the power to confront us and they must wait for our response.” The UK prime minister, Keir Starmer, congratulated Trump “on your historic election victory”. He added: “I look forward to working with you in the years ahead. As the closest of allies, we stand shoulder to shoulder in defence of our shared values of freedom, democracy and enterprise. From growth and security to innovation and tech, I know that the UK-US special relationship will continue to prosper on both sides of the Atlantic for years to come.” The former UK ambassador to Washington Nigel Sheinwald gave a less optimistic account of the UK government’s views of the four years ahead, telling the BBC: “The rest of the world is entitled to feel a great deal of apprehension [about Trump]. Not everywhere in the world. In Israel, in Russia, in North Korea, there will no doubt be hats being thrown in the air. Most of America’s allies in the world will be feeling extremely apprehensive.” The French president, Emmanuel Macron, who had a turbulent relationship with Trump in his first term, said: “Ready to work together as we have done for four years. With your convictions and with mine. With respect and ambition. For more peace and prosperity”. By contrast, France’s European affairs minister, Benjamin Haddad, had urged Europe to recognise that it could no longer depend on the vagaries of American politics for its defence, pushing the longstanding French view that the only solution lay in greater European defence cooperation. He warned that the “end of history” was over and “Europe needs to step up”. Macron’s staff said he would be consulting with European partners on how to strengthen European defence. Ursula von der Leyen, the EU Commision president and a likely future subject of Trump’s ire, said: “Let us work together on a transatlantic partnership that continues to deliver for our citizens. Millions of jobs and billions in trade and investment on each side of the Atlantic depend on the dynamism and stability of our economic relationship.” Behind the scenes, von der Leyen’s team has been preparing for a Trump victory for months, including by drawing up lists of US imports to Europe to target with tariffs if Trump imposes punitive duties on European goods to the US. Members of the populist European right were the most delighted. Geert Wilders, the Dutch populist leader, said: “Congratulations America! Never stop, always keep fighting and win elections!” Some of the most concerned reaction came from Germany, where the three-party coalition government led by Olaf Scholz is at risk of disintegrating and facing fresh elections. Both Trump and his vice-president, JD Vance, have been scathing about Germany’s failure to boost its defence budget, and its previous dependence on cheap Russian gas. In an assessment of Scholz’s failures to back Ukraine fully, Friedrich Merz, the leader of the Christian Democrat party, warned in a lengthy article: “European foreign and security policy is in a state of disarray.” He wrote that if Trump were elected, Europe “would have nothing to hide behind”, and said European leaders should have told Vladimir Putin that if he did not end his war of terror against the Ukrainian civilian population within 24 hours, “the range limits on weapons supplied to Ukraine will be lifted”. He claimed Scholz had instead “sought comfort in the past, and in the confidence associated with the solitary leadership of the United States”. In Poland – another country likely to be unnerved by Trump’s victory – the populist PiS has already called on the foreign minister, Radosław Sikorski, to resign because of his part-criticism of American isolationism. China, likely to be hit by tariffs and other trade restrictions, said it hoped for “peaceful coexistence” with the US as Trump was on the brink of victory. “We will continue to approach and handle China-US relations based on the principles of mutual respect, peaceful coexistence, and win-win cooperation,” the foreign ministry spokesperson, Mao Ning, told a regular briefing. But China is likely in the short term to be concerned about Trump’s plans to secure a peace deal with Putin over Ukraine. That will disturb Europeans most, however – including those in Baltic states that fear they may be next on Putin’s target list. Jonatan Vseviov, an Estonian diplomat and ambassador, said: “Nothing about Ukraine without Ukraine, nothing about Europe without Europe.” The chair of the Estonian foreign affairs committee, Marko Mihkelson, said: “Be ready to fight for yourself and your friends.” The former French ambassador to the US Gérard Araud said Europe had been hit by “an earthquake”, saying: “Ukraine, European security, trade … Everything is being called into question. We will call for a surge. I doubt it will come.”