A number of prominent commentators, including the ­historians Timothy Snyder and Sarah Churchwell, the former US secretary of state Madeleine Albright and the Berkeley public policy professor Robert Reich have been arguing for some time that Donald Trump is a fascist. The writer Rebecca Solnit has even called Trump’s ­supporters “Nazis”.

Look at his contempt for democracy, they say; his attacks on the press and the judiciary, his rabble-rousing, his intolerance of all who oppose him, his authoritarianism, his self-identification with foreign dictators and strongmen, his nationalism and “America first” foreign policy. Look at the way he spurns international organisations, treaties and agreements, his racism and encouragement of white supremacist groups, his incitement to violence on the streets of the US.

Certainly, these carry strong echoes of fascism. Hitler and Mussolini attacked the free press, poured scorn on the judiciary, urged their followers to attack and kill their opponents, and put a murderous racism at the heart of their ideology. They tore up treaties, abandoned international organisations, undermined and ultimately destroyed parliamentary democracy, and promoted a cult of their own personality that seduced millions of citizens into accepting them as great redeemers.

The temptation to draw parallels between Trump and the fascist leaders of the 20th century is understandable. How better to express the fear, loathing and contempt that Trump arouses in liberals than by comparing him to the ultimate political evil? But few who have described Trump as a fascist can be called real experts in the field, not even Snyder. The majority of genuine specialists, including the historians Roger Griffin, Matthew Feldman, Stanley Payne and Ruth Ben-Ghiat, agree that whatever else he is, Trump is not a fascist.

Fascism and Nazism were the creation of the First World War, which militarised society and – in the minds of their leaders and supporters – discredited liberal democracy by associating it with armed defeat. In Germany, the defeat was catastrophic, entailing large territorial losses, the emasculation of the country as a great power, and the payment of huge financial reparations to the Allies. Italy was on the winning side in 1918, but the expected gains from banding together with Britain, France and the US failed to materialise, and the country left the war with what historians have called “the mentality of a defeated nation”.

What drove fascism and Nazism was the desire to refight the First World War, but this time to win it. Preparing for war, arming for war, educating for war and fighting a war defined fascist theory and praxis. Hitler’s aim of conquering territory was put into effect immediately in 1933, as he rearmed Germany and set it on a path to invade neighbouring countries. By mid-1940, Nazi Germany had conquered Poland, Austria, Czechoslovakia and most of western Europe. The Third Reich lived for war, breathed war and promoted war without limits. Similarly, Mussolini’s central aim was to create a new “Roman empire”, beginning with the conquest of Ethiopia in 1935-36 and continuing with less successful attempts to subjugate countries around the Mediterranean, disastrously in the cases of Yugoslavia, Greece and North Africa.

For all of Trump’s hostility towards countries he perceives as enemies of the US, notably Iran, there is no indication that he sought a war with any foreign power, still less that he has been consumed by a desire for foreign conquest and the creation of an American empire. He is an isolationist, busy withdrawing US troops from foreign adventures, from Syria to Afghanistan. “America first” is not about launching foreign wars but disengaging from them.

Trump’s encouragement of violence against his opponents at home has been unsystematic. He has told his supporters to rough up reporters and suggested during the 2016 election campaign that his followers might like to make use of the Second Amendment of the US constitution (the right to bear arms) against Hillary Clinton. He has also described white supremacists as “good people”. But this bears no comparison to the hundreds of thousands of armed and uniformed stormtroopers and Squadristi that the Nazi and fascist leaders deployed on to the streets daily in the 1920s and early 1930s to intimidate, beat up, arrest, imprison and often kill political opponents.