First of all, communism would never had happened in Russia. Thus, there would be no cold war.
Second, Germany would be the ultimate power broker in Europe just like Germany is the strongest economic power in the European Union today. Millions of Europeans died and for what? In the end Europe is united through the European Union with Germany subsizing other European nations.
Third, Israel would not have been created since millions of Jews would able to live in a prosperous Europe, and the relations between the West and the Arab World would be much better since the United States is not a superpower, or global cop that Americans are today.
Forth, since the United States never mobilized for World War I or World War II, then why would the United States ever become a military superpower? The relations throughout the world would be much improved, we would never had joined the United Nations, or any kind of International body. America would be prosperous since we would be more free to trade with the whole world. We would not have to pay for our military, and our welfare state since communism and socialism never took place since there was no World War I.
Finally, The Death of the West would not take place. The Western civilization would be more traditionalist with christian roots, and the cultural marxists would not had gained control of our institutions. So there would be no such problems with immigration that the West have today.
This would be what history would had been like in an alternate Universe. World War I is such a waste, and the West have not been able to fully recover. I know that we would be able to recover if the West somehow discover their desire to live and matter in this world. Until then, it may be the end of the West as we know it. Thanks to the Great War.