President Donald Trump meets in Brussels today with leaders from the European Union and NATO, two pillars of the postwar transatlantic security order that he openly and routinely disparaged during his presidential election campaign.
First meetings between a new US president and his European and NATO counterparts are usually a routine affair, culminating in a declaration affirming the strength and vitality of their partnership. But expectations on both sides of the Atlantic have perhaps never been as low as they have been for this visit.
Rather than securing from Trump a firm and unequivocal commitment to the alliance and to continued US leadership in European security affairs, European leaders have more modest hopes. They may consider the meetings a success if there are no embarrassing public quarrels or early morning Twitter outbursts from the American president admonishing Europeans for allegedly not "meeting their financial obligations".
Brussels is the seventh stop on Trump's maiden overseas trip as president, a nine-day tour that included the Middle East and Europe.
The day will start with meetings with European Commission President Jean-Claude Juncker and European Council President Donald Tusk, followed by a "long lunch" with Emmanuel Macron, France's new president.
Given his ambivalence and sometimes open hostility towards the continent, European leaders are awaiting Trump's visit with nervous anticipation.
During last year's presidential campaign, for example, Trump called NATO "obsolete" and praised Britain's decision to leave the EU. Earlier this year, he called the EU "basically a vehicle for Germany" and predicted that other countries would follow Britain's lead and exit the bloc.
During France's presidential election earlier this month, he seemed to endorse Marine Le Pen, the candidate of the far-right National Front, who wanted to close French borders, leave the euro, and hold a referendum on France's EU membership.
Nigel Farage, UKIP member, MEP and the European political figure to whom Trump is perhaps personally closest, is a vocal advocate of Britain's EU exit.
Earlier this year, while listing threats facing the EU, such as China's actions in the South China Sea, renewed Russian assertiveness, instability in the Middle East, and radical Islamic terrorism, Tusk took the unprecedented step of including the new Trump administration, saying it threatened European stability.
Juncker, who is known for speaking his mind, said at an EU summit earlier this year that if Trump continued to promote other EU countries to follow Britain's lead and leave the EU, "I'm going to promote the independence of Ohio and the exit of Texas."
Trump's visit comes at a fraught moment for his presidency. His approval ratings have hit a new low, and former FBI director Robert Mueller has been appointed as special counsel to lead the investigation into possible collusion between the Trump campaign and Russia during last year's presidential election.
Questions over his ties to Russia continue to loom over his presidency, and further inquiries await him when he returns to Washington.
EU officials have warned Trump about the dangers of a disunited Europe, and in their meetings the international leaders will confront a number of complicated and potentially contentious issues, including terrorism, trade, and the future of NATO.
The recent suicide bombing in Manchester, the latest in a series of attacks in Europe over the past three years, is a grim reminder of the deadly terrorist threat facing the continent. British officials on Tuesday night raised the country's terrorism alert from "severe" to "critical," the highest level, for the first time in ten years, signalling that another attack could be imminent.
Negotiations over the Transatlantic Trade and Investment Partnership (TTIP) have ground to a halt since Trump's election. Trump's 2016 campaign routinely savaged multinational free trade agreements, and he withdrew the US from the Trans-Pacific Partnership (TPP), a free trade agreement signed by the US and 11 other countries, early in his administration.
As a candidate, Trump also vowed to decrease US obligations and commitments to American allies, including those in NATO. During a visit to the White House earlier this year, Trump reportedly handed German Chancellor Angela Merkel a "bill" for payments Germany owed to the US for its defence over many decades.
He has yet to publicly confirm, as other presidents have done since the Washington Treaty was signed nearly seven decades ago, that the US commitment to the alliance is inviolable.
Still, Trump's foreign policy seems to be slowly evolving into something roughly approximating a traditional Republican approach, mainly due to the influence of defence secretary James Mattis and national security advisor HR McMaster.
They seem to have convinced the president that NATO is important for American security and that a strong, united Europe is not contrary to US interests, as Trump had once seemed to suggest. In an April press conference with NATO Secretary General Jens Stoltenberg, Trump reversed his earlier comments on the alliance, saying that it was "no longer obsolete".
But European leaders are still trying to develop a fuller picture of Trump's thinking on NATO and Europe. An additional impediment to working with the new administration and understanding its orientation toward Europe is that many high-level positions that interface with Europe remain unfilled, including important positions in the Pentagon, undersecretaries of state, assistant secretary of state for Europe, and NATO ambassador.
Burden sharing and security
When Trump meets with the leaders of other NATO member states in the afternoon, two issues will be front and centre: burden sharing and counter-terrorism.
Disagreements over burden sharing are as old as the alliance itself, even if they have taken on greater vitriol under Trump. Since Dwight D Eisenhower, US presidents have pushed European countries to spend more on defence. All 28 NATO members have agreed to spend 2% of GDP on defence by 2024, but only five countries currently meet this target (the US, United Kingdom, Poland, Estonia and Greece).
Trump's approach to NATO is more transactional than that of past US presidents. Allies, he has seemed to suggest, must pay their fees to get membership benefits.
The US also wants NATO to formally join the US-led coalition fighting Islamic State, even though all NATO members are already involved at the national level. The alliance supports the mission, and has been training Iraqi security personnel in counter-terrorism tactics and strategy, but is not a formal member of the coalition.
Meanwhile, European leaders would like Trump to affirm the duties and obligations endowed in Article 5 of the Washington Treaty, which states that an attack on one member state shall be treated as an attack on them all.
And at a time European countries face the most tense security environment since the end of the Cold War, they would also like to see a sign that the administration is committed to US leadership in the security of the continent.
European countries reduced military spending dramatically after the Cold War, but tensions in Europe have been heating up over the past several years. Russia has displayed a new assertiveness, invading and annexing Crimea in 2014 and supporting anti-government rebels in eastern Ukraine.
Russian President Vladimir Putin has sought to undermine the EU and NATO by creating divisions in both organisations. Countries in Eastern Europe, such as Poland and the three Baltic States (Estonia, Latvia, and Lithuania) all of which are now NATO members, view Russian actions as a serious security threat.
In response, the US is increasing its military presence in Europe, a move that started before Trump became president. And NATO has begun deployment of four multinational battalions to the Baltic states and to Poland to reassure nervous allies.
Appalled but not afraid
Over the past four months, European leaders have shifted their views of Trump. They are now "more appalled than afraid". Trump is a newcomer to foreign policy and diplomacy, and his public statements show that he has little understanding of NATO or of the EU, nor does he seem to possess the interest or attention span for delving deeply into policy issues.
Four months into his presidency, European leaders continued to confront contradictory statements from the president. Even on core principles of the alliance, such as his commitment to Article 5 of the NATO Treaty, confusion reigns.
Still, they have no choice but to work with him, convincing him that the US will benefit from a strong NATO and a unified Europe.
Trump's visit to Brussels coincides with the opening of NATO's new headquarters, a gleaming US$1.1 billion steel-and-glass structure that took more than six years to build. Does the new facility symbolise the alliance's renewal in an era of rising geopolitical tensions or just an expensive effort to revive an increasingly hollow alliance? Today's meeting may tell us.