Allow me to make the following counterfactual: Suppose all immigration of Germans to America had been blocked from the start. Restrictionists would have had lots of arguments on their side: Germany was a hotbed of various collectivist ideologies that were inimical to American liberty: rabid Nationalism, Antisemitism, Communism, and National Socialism. IQ of German Americans is at best average. German immigrants only slowly assimilated and kept speaking German. And then alien habits like minors can drink beer. Etc.
Now let’s go back to 1940.
The US had a population of 132 million, Germany including Austria, Greater Germany, had a population of 79 million. So the US had a population 67% larger than that of Greater Germany.
Today about 17% of Americans claim German ancestry. Since there was only low immigration of Germans after World War II compared to other groups, the fraction should have been even higher in 1940. Assuming a quarter of US population in 1940 was of German descent, US population in the counterfactual would go down by 33 million to 99 million. Add the 33 million to the German population and you get 112 million. So now Greater Germany is 12% more populous than the US. The effect would have been like another major power of 66 million had entered the war on the side of the Axis.
And it gets worse: Forget about General Eisenhower, and get used to Generalfeldmarschall Eisenhauer. Same for Chester Nimitz for the Navy (now: Generaladmiral Nimitz) and Carl Andrew Spaatz for the Air Force (now: Generalfeldmarschall Karl Andreas Spatz). And more as a footnote: also no William Patrick Hitler receiving a Purple Heart for his service in the US Navy.
I will not expand on the counterfactual and make a claim that the Axis powers would have won the war. But then I am not sure I could argue the opposite. In a world of completely closed borders for citizens of Germany, Italy, and Japan, you would have to repatriate also millions of German emigrants and their descendents from the British Empire and another big chunk of the US population for Italian Americans.
How well did restrictionist predictions stand up in the real world? Letting a fifth column onto your soil could have disastrous consequences. Plenty of danger for the US, right?
Not really. Incidents of treason and disloyality were few and far between. The “Christmas Declaration by men and women of German ancestry” was more representative, signed among others by Babe Ruth:
“[W]e Americans of German descent raise our voices in denunciation of the Hitler policy of cold-blooded extermination of the Jews of Europe and against the barbarities committed by the Nazis against all other innocent peoples under their sway. These horrors … are, in particular, a challenge to those who, like ourselves are descendants of the Germany that once stood in the foremost ranks of civilization. … [We] utterly repudiate every thought and deed of Hitler and his Nazis … [and urge Germany] to overthrow a regime which is in the infamy of German history.“
Moral: You can look on immigrants as people who perhaps keep some allegiance to their old country and its culture. If that culture is thorougly collectivist as it was in Germany in 1940, that does not look good. Assimilation may be slow and incomplete.
However, that is looking on things only from the limited perspective of one country. If you look on them at a global scale, the effect is different. Even incomplete assimilation means having more people who are less committed to their previous views, and even some (and in the case of German Americans many) who are completely out of reach for collectivism. Open borders undermines collectivism.
So if you are concerned about liberty in the world long-term, you would want to have as many people as possible who are not stuck in collectivist societies and can be indoctrinated by totalitarian governments, and as many as possible who are exposed to liberty and have a chance to change their minds in an open society.
Good luck for the world that liberty went along with open borders for a long time.
The photograph of then-General Dwight D. Eisenhower speaking with paratroopers on the eve of D-Day, 1944 featured in the header is available at the Library of Congress.
I’m wondering about your math. Does “17% Germany ancestry” mean “17% of Americans are descended from one or more Germans” or “17% of Americans’ ancestors were German”? If the former, your math seems off. After all, if every American had precisely one German great-grandparent, 100% of us would have German ancestry. But that hardly means that the U.S. would have a population of 0 without German immigration.
Correct, that would be a stupid conclusion. Here is my reasoning which boils down to your second alternative.
The 17% is self-reported ancestry in the US census. It was also higher, I think 23% in 1990. I don’t really know what someone means by that. My first guess is that they have a German surname. So someone on their paternal line probably immigrated from Germany or Austria.
That can be both an underestimate and an overestimate. German names are also common in other countries, such as Switzerland, Luxemburg, parts of France, and other Central European countries. However, I’d guess that well over 80% of such names are found in Germany and in Austria.
On the other hand, there should also be many who have German surnames and who perhaps don’t claim German ancestry in the census. E. g. many Jewish names are German. Then probably many would apply a stricter criterion like: I know my grandparents immigrated from Germany (and else I would not be sure what my ancestry is) or: I only consider myself of German ancestry if most of my ancestors came from Germany.
Then there was some pressure to Anglicize German names. And about 15% of autochthonous Germans have Slavic names (usually with a German spelling, though), quite a few have French, Dutch or Italian names, which tells you something about how Germany has always been a country of immigration herself. Some names are not only German, e. g. Miller, so someone would not think it is a German name. Or they don’t care about the whole ancestry thing, which I find perfectly reasonable.
My hope is that self-reported ancestry roughly corresponds to “on my paternal line someone immigrated from Germany or Austria”. If you make some further assumptions which are debatable (e. g. equal birth rates in the US and Germany, 1:1 ratio of male to female immigrants), I’d say that my conclusion is correct that without immigration from Germany US population would be lower by the percentage with German ancestry, and German and Austrian population correspondingly higher. I am aiming for a very rough estimate, give or take a few million.
With no growth it would look like this:
– Generation 0: One couple immigrates from Germany. / They stay in Germany.
– Generation 1: They have a son and a daugther who are of German ancestry. / Two German children.
– Generation 2: The son marries someone and has two children of German ancestry, no matter of what ancestry his wife is. The daughter marries someone and has two children who may claim German ancestry or not depending on their father. However, if the father is of German ancestry, they already count for him, so it would be double-couting and they do not increase German ancestry on net. Else they are no more of German ancestry anyway. / Four German grandchildren minus two for double-counting.
So both the size of the population of Americans of German ancestry and of Germans in the counterfactual are the same. Of course, if there is some mixing in the US, the people in the counterfactual could not be the same persons as the Americans of German ancestry.
I admit that the part on Eisenhower, Nimitz (probably also a German name of Slavic origin, e. g. Czech: Němec = German) and Spaatz is not consistent with this. There I seem to assume someone of German ancestry is of pure German ancestry, so you could conclude that in the counterfactual the exact same person might have lived in Germany. Eisenhower’s ancestors had been in America since before the US had been established. So I guess it is highly improbably that he had only ancestors from Germany. But then that part was only meant as polemical and to scare Americans. 😉