  This line of argument invites a number of empirical and moral questions. Among the empirical questions, we might ask how confident we can be about the numbers and influence of the potential immigrants. Is the immigrants’ culture really that distinctive? And are we sure that these newcomers will resist assimilation? Also, how can we be sure that the cultural changes will be rapid and detrimental? Skeptics of this line of argument often object that people tend to (1) exaggerate how distinctive—and distinctively valuable—their existing cultures are (it is notoriously difficult to characterize “American” culture, for instance), (2) irrationally fear change, and (3) underestimate how much their culture is changing anyway, in the absence of immigration. Even if all of these descriptive objections can be definitively answered, important moral challenges remain. In particular, even if citizens have an understandable interest in maintaining cultural continuity, it remains an open question as to whether they have a corresponding moral right (and, if so, one might wonder about how weighty this right is). These questions matter, because outsiders may also have competing interests in, and/or rights to, enter the country in question, and thus they may permissibly be excluded only if the rights of insiders to preserve their cultural continuity outweigh any rights of foreigners to enter the political territory.