Many have noted similarities between Donald Trump’s political rise and that of the right wing in 1930s Europe. Yet recent events, such as the travel ban being smacked down by judges, have demonstrated that the political institutions of the US remain robust and that the President’s domestic agenda may be more constrained than some worried. But in the domain of foreign affairs the office of the president is granted much more latitude. Indeed, the prerogatives of the presidency, combined with Trump’s erratic and oversized personality, mean that the new president does not bear a resemblance with Hitler or Mussolini as much as he does Germany’s pre-WWI emperor, Kaiser Wilhelm II.

Like Trump, the Kaiser was an insecure and aggressive narcissist who allowed his mood to dictate many of his policy decisions, and while the domestic effects of these traits could be limited by the quasi-democratic institutions of the German Reich, in the foreign policy arena his personality wreaked havoc.

Many of the parallels between the Kaiser and Donald Trump are darkly comic. Trump displays a fragile sensitivity, lashing out at those who mock or undermine him while also lavishing praise on any figure who flatters or supports him, from world leaders to innocuous teenagers. In his time, the leader of Europe’s military and economic powerhouse was equally notorious for his outbursts and gaffes. On one occasion, the boat-mad Kaiser posted a notice in the clubhouse at Britain’s prestigious national yachting regatta complaining that the handicapping system in use was “perfectly appalling” despite the fact that his yacht actually won the race (one is reminded of Trump complaining that his own election was rigged).

The controversial orders Donald Trump has already issued Show all 9 1 /9 The controversial orders Donald Trump has already issued The controversial orders Donald Trump has already issued Trump and the media White House Press Secretary Sean Spicer takes questions during the daily press briefing Getty Images The controversial orders Donald Trump has already issued Trump and the Trans-Pacific Partnership Union leaders applaud US President Donald Trump for signing an executive order withdrawing the US from the Trans-Pacific Partnership negotiations during a meeting in the Roosevelt Room of the White House in Washington DC. Mr Trump issued a presidential memorandum in January announcing that the US would withdraw from the trade deal Getty The controversial orders Donald Trump has already issued Trump and the Mexico wall A US Border Patrol vehicle sits waiting for illegal immigrants at a fence opening near the US-Mexico border near McAllen, Texas. The number of incoming immigrants has surged ahead of the upcoming Presidential inauguration of Donald Trump, who has pledged to build a wall along the US-Mexico border. A signature campaign promise, Mr Trump outlined his intention to build a border wall on the US-Mexico border days after taking office Getty Images The controversial orders Donald Trump has already issued Trump and abortion US President Donald Trump signs an executive order as Chief of Staff Reince Priebus looks on in the Oval Office of the White House. Mr Trump reinstated a ban on American financial aide being granted to non-governmental organizations that provide abortion counseling, provide abortion referrals, or advocate for abortion access outside of the United States Getty Images The controversial orders Donald Trump has already issued Trump and the Dakota Access pipeline Opponents of the Keystone XL and Dakota Access pipelines hold a rally as they protest US President Donald Trump's executive orders advancing their construction, at Columbus Circle in New York. US President Donald Trump signed executive orders reviving the construction of two controversial oil pipelines, but said the projects would be subject to renegotiation Getty Images The controversial orders Donald Trump has already issued Trump and 'Obamacare' Nancy Pelosi who is the minority leader of the House of Representatives speaks beside House Democrats at an event to protect the Affordable Care Act in Los Angeles, California. US President Donald Trump's effort to make good on his campaign promise to repeal and replace the healthcare law failed when Republicans failed to get enough votes. Mr Trump has promised to revisit the matter Getty Images The controversial orders Donald Trump has already issued Donald Trump and 'sanctuary cities' US President Donald Trump signed an executive order in January threatening to pull funding for so-called "sanctuary cities" if they do not comply with federal immigration law AP The controversial orders Donald Trump has already issued Trump and the travel ban US President Donald Trump has attempted twice to restrict travel into the United States from several predominantly Muslim countries. The first attempt, in February, was met with swift opposition from protesters who flocked to airports around the country. That travel ban was later blocked by the Ninth Circuit Court of Appeals. The second ban was blocked by a federal judge a day before it was scheduled to be implemented in mid-March SANDY HUFFAKER/AFP/Getty Images The controversial orders Donald Trump has already issued Trump and climate change US President Donald Trump sought to dismantle several of his predecessor's actions on climate change in March. His order instructed the Environmental Protection Agency to reevaluate the Clean Power Plan, which would cap power plant emissions Shannon Stapleton/Reuters

Foreign diplomats sympathised with the German foreign policy establishment. After one of Wilhelm’s outbursts the Prince of Wales told the German ambassador: “I don’t envy that Sisyphus job you have with the Kaiser.” This sort of benevolent eye-rolling is typical of how many modern commentators have interpreted Trump’s frequent outbursts. Whether he is threatening China, intimidating businesses, or humiliating other TV celebrities some share a sentiment that Trump’s blustering might be managed, ignored, and worked around. But we should temper that assumption as the behaviour of Trump – like the Kaiser – can have meaningful consequences.

First, foreign policy by stream of consciousness may be ignored by diplomats but it will not be ignored by domestic audiences. For instance, during his reign the Kaiser allowed his peevish envy of Britain to ruin Germany’s image with ordinary Britons. In an infamous 1908 interview with the Daily Telegraph the Kaiser explained that Germany could have attacked Britain during the Boer War but he had decided against it, that Britain’s success in that war was due to a secret plan of his own devising, and that one day Britain would rely on Germany for its naval security. Such a blatant insult to British ability and strength provoked outrage in the UK and could not be simply swept under the rug. In response to domestic outcry British foreign policy hardened against Germany. The Kaiser’s chancellor lamented that this interview demonstrated “more than any previous manifestation of the kind, the Emperor’s intellectual extravagance, his incoherent regard of facts, his complete lack of political moderation and balance, combined with an excessive urge towards… display.”

Likewise, Trump’s supporters may hope that other world leaders will ignore Trump’s excesses but this assumes they do not have foreign publics they must placate. Whether they wish to or not, they may feel the need to add fuel to the fires he lights.

Chuck Schumer says that either way these wire-tapping allegations are bad news for Donald Trump

Second, an unconstrained narcissist in power is dangerous as narcissists are easily manipulated. Despite disliking him, British Foreign Office mandarins soon understood that if they wished to get on the militarily-obsessed Kaiser’s good side – he often changed uniform six times a day – they only had to make him an honorary member of a military regiment. But the Kaiser’s naïveté was also exploited in more nefarious ways. In 1905 the German chancellor convinced Wilhelm that his long held wish to visit Tangiers (in French “protected” Morocco) would be politically insignificant. On the contrary, it triggered a major great power crisis that resulted in the solidifying of an increasingly antagonistic Anglo-French alliance.

Trump may be equally susceptible to such manipulation; some report that his decision to suddenly break with four decades of bipartisan policy on China may have been encouraged by a pro-Taiwan lobby group. Increasingly, the evidence suggests that the new president is susceptible to the machinations of self-interested actors, both foreign and domestic.

Third, volatile and bombastic leadership is inherently bad for foreign policy. The Kaiser’s Germany was incredibly powerful but it was not invincible. Her exposed position in the centre of Europe could only be guaranteed by supporting Austria-Hungary, securing Russian cooperation regarding France, and by ensuring British indifference to Germany’s existence. These policies required careful management and diplomatic circumspection. The Kaiser possessed neither. He did not wish Germany to simply exist; he wished it – in the words of one chancellor – to “have its place in the sun.” This policy of Weltpolitik was as destabilising as it was self-defeating. By refusing to accept the limits of German influence, the Kaiser drove the French and Russians together. By deciding to commit Germany to an expensive and strategically bankrupt policy of naval build-up he made an irascible foe of its traditional ally, Britain. In short, by wishing to make Germany great again the Kaiser set it on the path toward self-immolation.

The current American-led system faces similar dangers with Trump at its helm. Undoubtedly the modern architecture of international politics is far more durable than that of 19th century, mediated as it is through institutions such as NATO, the WTO, and the UN. Yet this architecture is still fundamentally dependent one key principle: that the US can be trusted. And in his narrow desire to put "America First", Trump looks certain to demolish this principle. Trump supporters encourage people not to take everything Trump says seriously but the rest of the world cannot take that chance. Whether Trump is exaggerating US ambivalence to NATO or not, Europeans cannot wait to figure this out and will have to ensure their interests.

Similarly, perhaps Trump is sincere when he changed his position on the One China policy or maybe he is not. Either way, China is now rattled. Indeed, his cavalier attitude has already worried Japan, emboldened Iranian hardliners, and of course, played into Russian strategic designs.

Such reckless leadership may get its comeuppance. When Archduke Franz Ferdinand was murdered by Serbian terrorists in June 1914 the impetuous Kaiser issued the infamous ‘blank check’: a promise to support any action that Austria-Hungary chose to undertake regardless of the consequences. The next day he went yachting for three weeks. Meanwhile, Austrian-Hungarian generals and foreign governments took his guarantee literally not symbolically and began planning accordingly. By the time the Kaiser realised his error and tried to rescind the check it was too late. The wheels of war were already in motion and Europe was to begin its thirty-year plunge into darkness.

What the Kaiser had realised, far too late, was that what he said and did mattered, whether he meant it to or not. Let us hope President Trump learns this lesson far sooner.