America goes cash and carry in ww1.
Now the entente has to pay for their imports in hard currency and without credit, they start to run out of hard currency by 1915 at the latest 1916 to pay for imported materials needed for the war.
Without the need to recover wartime debts America is under less pressure to make sure the entente wins so the loans can be repaid.
Germany might get a win against France and Russia but has no way of invading the UK who could continue a blockade.
Wartime shortage in the UK could lead to civil unrest along with a rebellion in Ireland could lead to the UK doing a deal with the central powers or a white peace could happen when the British and French see the realise America is not going to help.
Germans might be smuggling arms to Ireland.
A shorter war might mean ottoman empire surviving and no communist in Russia as Lenin never is sent by the Germans to Russia and an early peace deal allows Russia to stop the revolution.
Spanish flu might not happen or spread much more slowly.
Europe is still in bad shape after all the spending by both sides after the war and in its possible Germany will lose much of their overseas colonies.
Without the communist in the Soviets union, the Ukraine could remain a major exporter of grain affecting the price of grain worldwide and reducing the need to plant more wheat in the US and reduce the effect of the dust bowl due to lower wheat prices.