For many people, Mr Donald Trump's big speech in Poland earlier this month was a welcome reassurance. Here was the President, for the first time, sounding the way a president of the United States was supposed to sound - like a statesman.
In his most substantial foreign policy speech to date, he abandoned the "America First" talk which has led to fears of a return to the isolationist America of the 1930s. Instead he stood in front of a memorial to the 1944 Warsaw Uprising against the Nazis and offered a broad vision of America as the leader of a grand international coalition of nations.
He reaffirmed America's determination to uphold, at any cost, the core values he declared this coalition to hold in common. "We will never back down" in defending these values, he said, thus completely repudiating his own Secretary of State Rex Tillerson who had earlier told his own State Department not to let such values get in the way of American interests.
And most importantly, he seemed to reaffirm America's all-important security commitments to Europe under Article 5 of Nato, which he had so pointedly refused to do a few weeks earlier in Brussels. "We stand firmly behind Article 5," he said.
All this explains why at first glance so many people have welcomed the speech as signalling a return to the kind of orthodox foreign policy that Mr Trump had until now seemed so eager to abandon. But a closer look is less reassuring. There are real uncertainties about what Mr Trump was committing America to do on the world stage, and doubts whether that commitment can be taken seriously.
Start with the distinctive way he defined America's global mission. This was very different from anything seen for the past 25 years. Since superpower rivalry ended with the Cold War, American leaders have defined America's international mission expansively and inclusively. They have promoted a vision of a world order united by shared values and aspirations under US leadership.
That order was open to any region, country and people who cared to join it - a truly global vision - and America's mission was to persuade as many people and regions as possible to join it. Even the War on Terror aimed ultimately to bring regions like the Middle East fully into this unified, US-led international order.
Mr Trump's vision in Warsaw was much narrower, much darker and more exclusionary. He spoke of "The West", which he identified throughout the speech narrowly and quite specifically as the nations of Europe and America. These nations, he said, "are the greatest community. There is nothing like our community of nations. The world has never known anything like our community of nations. We write symphonies. We pursue innovation. We celebrate our ancient heroes, embrace our timeless traditions and customs, and always seek to explore and discover brand-new frontiers".
And these nations, he said, face "dire threats to our security and to our way of life. You see what's happening out there. They are threats. We will confront them. We will win. But they are threats".
He added: "The fundamental question of our time is whether the West has the will to survive. Do we have the confidence in our values to defend them at any cost?"
The global role that Mr Trump committed America to pursue in Warsaw was thus the defence of the narrow, exclusive, xenophobic and arguably racially-based idea of the West from the enemies which he claims encircle it.
And what are those threats?
Clearly they include terrorism, but they go much further than that. Mr Trump spoke vaguely of threats "from the South and the East", and also from within the West's own societies. The impression his speech conveyed was that everyone who does not share his vision of the West's values is an enemy of America.
All this leaves many unsettling questions. One of the most obvious is how does Asia fit into Mr Trump's world view?
Mr Trump has defined America's international role as the defence of the culture, civilisation and values which he claims to be exclusive to Europe and America, against any and all challenges from other regions, other civilisations and other value sets.
Is that image compatible with the kind of role that America has played in Asia until now? Is it compatible with a constructive and stabilising US regional role in future? It is hard to see how.
A broader question is whether Mr Trump's speech in Warsaw should be taken seriously.
As he himself said in Warsaw, "words are easy, but actions are what matters". Saying the US stands behind Article 5 is one thing, but really committing the US to the massive costs and risks of a war in Europe to confront any future Russian aggression against, say, the Baltic States would be quite another.
Nothing he said in Warsaw, or anywhere else, suggests that he has begun to contemplate the real strategic choices that America must confront as it defines its global role in an era which does indeed pose many challenges for American power and leadership.
Indeed his Warsaw speech is probably best seen as simply an extension of the style of domestic demagoguery that won him the White House last year. It had all the elements of one of his famous campaign rallies at home. He cultivated his audience's anxieties by conjuring a narrow sense of shared identity threatened by a host of vaguely-defined enemies, and promised bold solutions which won't be implemented.
Perhaps we should not be surprised that Mr Trump and his advisers believed that a style of politics that worked so well for him at home would also work abroad.
We should, however, be surprised that so many people who should know better mistook this crude politics for statesmanship.
Hugh White is professor of strategic studies at the Australian National University in Canberra.
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