One can become virtually xenophobic in order to protect or claim to protect one's own hospitality

The perversion and pervertibility of this law (which is also a law of hospitality) is that one can become virtually xenophobic in order to protect or claim to protect one's own hospitality, the own home that makes possible one's own hospitality. [...] I want to be master at home (ipse, potis, potens, head of house, we have seen all that), to be able to receive whomever I like there. Anyone who encroaches on my "at home," on my ipseity, on my power of hospitality, on my sovereignty as host, I start to regard as an undesirable foreigner, and virtually as an enemy. This other becomes a hostile subject, and I risk becoming their hostage.

Jacques Derrida, Of Hospitality (Stanford University Press, 2000) pp. 53-55

The law of absolute hospitality commands a break with hospitality by right

A proper name is never purely idividual.

If we wanted to pause for a moment on this significant fact, we would have to note once again a paradox or a contradiction: this right to hospitality offered to a foreigner "as a family," represented and protected by his or her family name, is at once what makes hospitality possible, or the hospitable relationship to the foreigner possible, but by the same token that limits and prohibits it. Because hospitality, in this situation, is not offered to an anonymous new arrival and someone who has neither name, nor patronym, nor family, nor social status, and who is therefore treated not as a foreigner but as another barbarian. We have alluded to this: the difference, one of the subtle and sometimes ungraspable differences between the foreigner and the absolute other is that the latter cannot have a name or a family name; the absolute or unconditional hospitality I would like to offer him or her presupposes a break with hospitality in the ordinary sense, with conditional hospitality, with the right to or pact of hospitality. In saying this, once more, we are taking account of an irreducible pervertibility. The law of hospitality, the express law that governs the general concept of hospitality, appears as a paradoxical law, pervertible or perverting. It seems to dictate that absolute hospitality should break with the law of hospitality as right or duty, with the "pact" of hospitality. To put it in different terms, absolute hospitality requires that I open up my home and that I give not only to the foreigner (provided with a family name, with the social status of being a foreigner, etc.), but to the absolute, unknown, anonymous other, and that I give place to them, that I let them come, that I let them arrive, and take place in the place I offer them, without asking of them either reciprocity (entering into a pact) or even their names. The law of absolute hospitality commands a break with hospitality by right, with law or justice as rights.

Jacques Derrida, Of Hospitality (Stanford University Press, 2000) pp. 23-25

The thing that is so worrying about the character of the immigrant is the emigrant

Perhaps the reason why immigrants worry settled people so much (and often so abstractly) is that they expose the relative nature of certainties inscribed in the soil: the thing that is so worrying and fascinating about the character of the immigrant is the emigrant. The state of contemporary Europe certainly forces us to envisage the 'return' of nationalisms. Perhaps, though, we should pay more attention to the aspects of this 'return' that seem essentially to express rejection of the collective order: obviously the model of national identity is available to give form to this rejection, but it is the individual image (the image of the free individual course) that animates and gives meaning to the model today, and may weaken it tomorrow.

Marc Augé, Non-Places (Verso, 2008) p. 97

Borders do not acknowledge and register an already existing estrangement

As Frederick Barth explained, borders do not acknowledge and register the already existing estrangement; they are drawn, as a rule, before the estrangement is brought about. First there is a conflict, a desperate attempt to set 'us' apart from 'them'; then the traits keenly spied out among 'them' are taken to be the proof and the source of a strangehood that bears no conciliation. Human beings being as they are multi-faceted creatures having many attributes, it is not difficult to find such traits once the search has started in earnest.

Zygmunt Bauman, Liquid Modernity (Polity Press, 2012) p. 177