Greetings! We have had a fair few questions on AH in the past few months about America's entry into the First World War, but this is certainly the first that I have answered about why it was neutral in the first place. The answer there is slightly easier than the answer to the second bit of the question. Let's start with that first and then explore the historiographical arguments for why this neutrality was formally broken in 1917. As a general bit of background research, or indeed further watching, consider viewing this great lecture from American historian Michael S. Neiberg on the US's war from 1914-1917.

Note: Though the US formally entered the war on the side of the Entente powers in April 1917, it was by no means "isolationist" up until then. u/IlluminatiRex and myself delve into how involved America was with the Great War before 1917 in this thread here.

To explain its neutrality at the outbreak of war in 1914, we can point to the belief that the American government at the time was not interested in taking part. Now of course, that statement is an oversimplification of various sentiments, opinions, and individual reasons as to why the US remained neutral until 1917, but it does help as a sort of "umbrella motive" if you will. To expand upon that, the First World War erupted in Europe due to a...fairly complex and messy sequence of events that were sparked by the assassination of Archduke Franz Ferdinand in Sarajevo (June 28th, 1914). Put plainly, the American government had no connection to these events. It did not, unlike Germany, France, or Russia, have any standing mutual defense pacts with the to-be combatant nations. It did not feel as though it was particularly connected with the ethnic tensions that had been plaguing the Balkans and the Austro-Hungarian Empire in the past few decades, and it had no obligation to come to the aid of a particular European country when it was invaded (as Britain claimed when it came to Belgium's aid on the 4th of August).

The American people as whole also saw no reason for their country to get involved with the war in Europe. Granted there were certainly minority voices at the outbreak of war and up until 1917 which were pro-Central Powers or pro-Entente, but America in 1914 was playing the role of "spectator", cheering on neither side until it became more and more apparent that there was a need to take sides in the war. More on that in the next section, and the various reasons which propelled the US into war.

1917

The cultural argument: this motivator has often been scrutinised by historians, and the general consensus is that there were no significant cultural sentiments which propelled the US Government to declare war against Germany rather than Britain and France. President Woodrow Wilson viewed both the French and the British as "old-world imperialists", and especially despised the British governments "navalism" (a reference to its use of the Royal Navy to aggressively conquer and control colonies). To Wilson, this "British navalism" was just as bad as "German militarism", and much of the American public also shared this viewpoint at the beginning of the war in 1914.

The American public itself was divided by 1916, with two clear sides forming (albeit minority sides, as neutrality remained the major sentiment up until 1917). On the one hand, America was full of ethnic German-Americans, whose vote Wilson may have wished to secure by promising neutrality in the coming years. There were also Irish voters in the Eastern cities, whose fury at the British oppression during the 1916 Easter Uprising meant they were against the US joining an old enemy. On the other hand, the Pro-British side was formed of the "Wasp" (White Anglo-Saxon Protestant, as Michael Howard terms it) supremacy on the east coast, as well as notable figures such as newspaper magnate William Randolph Hearst and ex-President Theodore Roosevelt. Neither side could claim the majority up until 1917, so America had to remain politically neutral in the whole affair. Thus, was there a cultural link between the US and the Entente that weighed in heavily on the intervention debate? Not to a significant degree. The main "cultural" factor (if it can termed as such) which may have played a role was the news of German war crimes, most notably the atrocious acts committed by German troops in their occupation of Belgium, and their deliberate destruction of many cultural/religious sites in the Low Countries. News of these atrocities is believed to have tipped the scales further in favour of American intervention on the Entente side, though as we shall discuss next, the economic factor was a considerable one.

There was indeed an economic reason behind the US entering the First World War, but do not be swayed into thinking that it actively got involved in order to expand its economic interests or purely to enhance its economic power in the world. Economically, America was most certainly not neutral prior to 1917, though this was mostly due to wartime fact rather than commercial preference. France and Britain relied to a considerable extent on shipments of American goods to sustain the war effort, and the US was more than willing to extend credit to these countries and continue the flow of materiel. On the other hand, the Royal Navy's blockade of Germany meant that no US goods were able to flow into that country. This of course created a natural "tilt" towards the Entente Powers, and gave the traders in America more to worry about as the war dragged on. Michael Howard sums up this economical perspective well:

"Yet as the war went on an increasing amount of that business [America getting involved in war] consisted in supplying war material to the Allies - not necessarily out of ideological sympathy, but because they could not get it to the Germans. If that trade were interrupted, then the war would become their business, whether they like it or not."

This fear of interrupted trade had been realised in 1915 when the Lusitania was sunk. Though she had been carrying ammunition in a secret hold compartment, the Germans were forced to scale down their submarine offensives in the Atlantic and operate by "cruiser warfare rules", by which all passengers had to be warned of an attack, allowed to abandon ship, and pointed in the direction of the nearest port (idealistic at best, downright impossible and impractical at worst).

With the recent historiographical work on the matter, we now know that key advisers and business officials in America did indeed share concerns about a German victory endangering the economic expansion and security of the United States. In the 1920s and 1930s, "revisionist" and "New Left" historians contested that the economic security of the United States, coupled with the threat to that security posed by German unrestricted submarine warfare, led the American government to choose intervention over neutrality.

There is certainly some merit to the economic argument. The war-induced exports boom to the Entente Powers was a great boon to the economic power of the United States, and its businesses did not mind being unable to trade with Germany so long as Britain and France continued to place orders for resources and war materiels with them. By 1917, exports alone made up 11% of America's Gross National Product (GNP), and 80% of that trade was destined for Entente ports in Britain, France, and their colonies. There is a positive correlation between the US public's outcry at German submarine warfare and the rising export boom throughout the war.

In 1916 for example, when both exports and the German submarine threat were far greater, Wilson threatened to sever relations with Germany if they continued, and the German government actually abided by this warning, suspending unrestricted submarine warfare until January 1917.

Yet to simply leave this response with the affirmation that economic reasons did play a role in the US's entry into the First World War would be to gloss over other aspects which played an equal (if not greater) role. Let us start by looking at the geopolitical fears of the US in 1916-1917, and their impact on the case for war.

Part 1 of 2