Every European power wanted to go to war for any number of (usually) stupid reasons. Germany gets to take the fall for firing the first shot, but without the eager way in which Britain, France, Italy, Austria-Hungary, Turkey, and even Russia picked sides and jumped in, the war would have been a local brush fire.
As late as a week before, Asquith was still thinking that Britain would stand aside from the coming war.
It was possible for the war to be started by any number of circumstances, sure, but France didn’t seize Spanish possessions in Morocco; Italy didn’t try to reclaim Savoy. Austria did try to finish consolidating their buffer empire against the Ottomans, and Germany was the first one to pre-emptively declare war against other major powers without an explicit cause.
Which is why I noted that they took the fall. It is unlikely that Britain would have initiated an attack on the Continent, (although attacks on German Africa are less unlikely), but the idea that by 1925 France would have tried to recover land lost after the 1870 conflict or Italy would have been willing to seize more of the northern Adriatic are not implausible. And looking at the various (un)diplomatic exchanges among Britain, France, Germany, and others leading up to the war in 1914 indicate that all the major parties were desirous of a war.
Of course Germany gets to take the fall for starting the war, that’s because they started the war. A local brushfire between whom exactly? Austria-Hungary and Serbia? That wasn’t going to happen without drawing Russia into it, which Austria-Hungary wasn’t going to do without the backing of Germany. Which Germany gladly gave with its blank check to Austria-Hungary. In one of that centuries greatest diplomatic screw-ups, making it clear that Germany was going to have its war regardless, Germany accidentally handed Russia a declaration of war giving its reason for doing so that Russia hadn’t ceased its mobilization and that it hadn’t deemed it necessary to respond to German demands that it ceased doing so. The German ambassador to Russia had forgotten to give only the reason that applied, so the declaration read:
To ‘protect’ itself from Russia, Germany then proceeded to invade Belgium, and demand France demobilize and surrender its border fortifications to German occupation for the duration of the war - a demand it knew was beyond unacceptable; German troops marching through Belgium were sweeping through to outflank the French border defenses and invade France through Belgium. It was only the invasion of Belgium that cemented Britain to commit to the war, as it was bound by the Treaty of London to defend Belgium. Germany’s only war plan in the event of a European war was to immediately invade Belgium, Luxemburg and France. From the moment Germany announced general mobilization it was committed to war, and a war starting this way as it was going to start delivering its armies to the Belgian border. Germany was the only nation that inexorably committed itself to war with no possibility of actual negotiations by the act of declaring mobilization. The Ottoman Empire, far from eagerly picking sides and jumping in declared itself neutral and was only persuaded to jump in after Germany bribed it with by giving it the battlecruiser Goeben and the light cruiser Breslau as well as pledging to provide gold loans to finance the war. Italy, even further from jumping right in, declared its neutrality, and withdrew from the Triple Alliance with Germany and Austria-Hungary on the grounds that it was defensive in nature. Italy wouldn’t join the war until 1915.
Sure, the war was greeting with a naïve enthusiasm and popularity by all nations when it began. That doesn’t absolve Germany from beginning it, or make them the fall guy for starting it on the grounds that it isn’t implausible that France might have hypothetically gone to war over Alsace-Lorraine by 1925 if Germany hadn’t started the war in 1914.