Donald Trump’s “America First” philosophy marks a profound break with the liberal and internationalist ideas that have shaped US foreign policy since the second world war. Thomas Wright of the Brookings Institution was one of the first scholars to attempt a serious analysis of Trump’s views on foreign policy. In his new book, Wright makes a convincing case that an “America First” strategy, as advocated by President Trump, will harm both the world and the US itself.

All Measures Short of War was clearly originally conceived of as a potential handbook for an incoming Clinton administration. The author wryly acknowledges that his recommendations for a reinvigorated US commitment to the liberal international order are unlikely to be met with favour in the Trump White House. Nonetheless, Wright’s book is still an immensely useful and lucid analysis of the current global balance of power — and therefore of the challenges that will face any occupant of the Oval Office.

One of the most convincing insights in the book is that the “world order” is, in fact, a series of regional orders that are underpinned by US power. As Wright puts it: “The most important piece of the liberal order is not the United Nations or international financial institutions . . . It is healthy regional orders . . . If those regional orders fall apart, so will the global order.” The difficulty is that the regional orders in Europe, Asia and the Middle East are, indeed, under immense pressure. As Wright shows, the fond hope of successive US presidents was that Russia and China would buy into a US-led world order, perceiving it to be ultimately beneficial to their own economic interests. There were even hopes in America that the Middle East would “converge” with the western model — hopes that were briefly stoked by the Arab Spring.

Faced with all this global disorder, one possible American reaction would to throw up their hands in horror and head home. This indeed seems to be the instinct of Trump, who has repeatedly questioned the idea that it is in America’s interests to sustain its alliance systems around the world, on the current model. Trump has famously argued that the US is being duped by foreign countries that free-ride off the American security guarantee — while trading unfairly with their protector.

Wright’s book is a convincing refutation of the idea that America might be better off if it abandoned the idea of a liberal global order and acquiesced in the creation of regional spheres of influence for Russia, China and (possibly) Iran. “The liberal international order has been tremendously successful in safeguarding US interests while bolstering the peace and prosperity of most of the rest of the world,” he argues. By contrast, a world organised around regional spheres of influence would be much less stable and would encourage China, Russia and others to test US resolve. In such a world, trade would diminish and democracy would retreat. “The United States would quickly find itself embroiled in conflict and from a much weaker position than it now enjoys.”