  No one can deny the moral importance of protecting innocent civilians from terrorist attack, but critics have questioned whether restricting immigration is in fact likely to provide the desired security. Chandran Kukathas (2014), for instance, raises two important concerns. First, he notes that, while laws to limit immigration may well decrease legal immigration, they will not realistically be able to eliminate all illegal immigrants. And this point is relevant, of course, because foreign terrorists who feel so passionately about their causes so as to be willing to carry out terrorist missions are not likely to be dissuaded from doing so by the illegality of entering the country whose citizens they seek to attack. Second, even if a state could somehow eliminate all legal and illegal immigration, this would not be enough because foreigners routinely enter countries, not as immigrants, but for shorter periods as tourists, guest workers, visiting students, or for short business trips. Thus, even if a country somehow managed to preclude all immigration, it could not reasonably hope to exclude all foreign terrorists unless it also restricted the flow of temporary visitors.