Yes, it would seem that this is the kind of argument used in countries like Bulgaria, Croatia, Estonia, Finland, Greece, Hungary, Israel, Malaysia, Romania, Serbia, and Turkey, where citizenship is determined with the help of Ethno-nationalist arguments in the law (re. one's origins in a given country). In some parts of the US before WWI and WWII, Germans could not marry the Irish, or the Italians could not mary the Portuguese, and other ethnic restrictions were required. Jews aren't supposed to marry Goyim. There will always be ethnic preferences, though I wonder about the problems with politicizing this, for the sake of ethno-nationalism. According to research with dog breeds, and inbred human communities, marying outside of one's breed or family or ethnicity produces much stronger, smarter, and in some cases, more attractive offspring. See for example the typical Brazilian, who is often some combination of German, Japanese, Spanish, African, and Native American. Really aattractive people. But I digress. Thanks for the response.