Insofar as human happiness is achievable, the clear verdict of history is that it is most readily achievable in societies based on the principles of liberal democracy. That is, societies with democratically elected representative governments that respect individual liberties, and which maintain satisfactorily high standards of social justice and economic equity. Examples of liberal democracies would be France, Germany, The Netherlands, the UK, the Scandinavian countries, Australia, New Zealand, Japan, Canada, and (decreasingly) the United States. Liberal democratic societies minimize the greatest obstacles to human flourishing, such as arbitrary, oppressive, and dictatorial government, gross inequalities, intolerance of dissent, racial, ethnic, religious, and other forms of discrimination, extreme poverty, and denial of opportunity. No society can guarantee happiness, of course, since achieving happiness requires personal responsibility and effort as well. However, a liberal democracy can create the conditions in which effort is rewarded rather than stymied. Liberal democracies can provide some of the necessary but not the sufficient conditions for happiness.

Secularism is a necessary corollary of liberal democracy. Secularism, as a tenet of liberal democracy, I understand as follows: No religion is to be mandatory or exclusive and no religion is permitted to exercise hegemonic dominance over other religions. The power, prestige, or authority of the state is not to be used to promote any species of belief or nonbelief over others. The former Soviet Union, by declaring atheism the official doctrine, was just as much opposed to liberal democratic values as is Iran’s imposition of Shiite Islam. Therefore, all faiths, as well as all varieties of nonbelief, must be allowed to flourish. Each doctrine is allowed free exercise of its beliefs, with the only requirement that such exercise does not abridge the fundamental rights of others.

It is this last point that ushers in the paradox. What if the tenets of one religion require that its adherents seek to abridge the rights of others? In that case, a liberal democracy, in virtue of its very tolerance, is led to accept into itself those who are not tolerant, and whose beliefs do require the hegemonic dominance of that religion or other violations of basic rights. In other words, a liberal democracy will willingly permit those who are ideologically opposed to liberal democracy. Those with an ideology opposed to the tenets of liberal democracy will then claim that the liberal democracy is oppressing them by preventing them from exercising their faith. The central paradox of liberal democracy is therefore this: The ideals of tolerance of a liberal democracy open such societies to those who are not tolerant and who, by conviction, are opposed to the ideals of liberal democracy.

Here is a case in point: Some years ago, a trip to the airport was even more stressful. As you hurried to your gate, an earnest figure in unusual garb would aggressively step in your way and attempt to prevent you from passing. Members of the Hare Krishna sect would swarm over airports, blocking the paths of travelers and assertively asking for donations in exchange for books of scripture. They could be quite pushy about it. Anyone that had to go to airports in that era loved the hilarious and deeply satisfying scene from the movie Airplane, where Robert Stack punched, karate-chopped, and judo-flipped airport cultists. Frankly, they were a pain in the neck.

Eventually, the courts stepped in and required anyone soliciting donations to stand behind counters rather than impede the flow of foot traffic. The Krishnas complained, no doubt truly, that the tenets of their religion required them to aggressively proselytize and seek donations. However, the courts decided that the right to freedom of movement and non-harassment in a public space was sufficiently strong to permit the restriction of the Krishnas’ religious freedom. Krishnas were not forbidden to proselytize, but not in ways that impeded or harassed people. Needless to say, the Krishnas quickly disappeared from airports.

Other cases point out the paradox more starkly. In 2004, the Dutch filmmaker Theo van Gogh was murdered by a Dutch-Moroccan citizen—a Muslim who was offended by van Gogh’s film Submission about the status of women in Islamic societies. The Netherlands, as a very liberal, open, and tolerant society, had permitted the immigration of radical Muslims for whom free speech was not an ideal, and in whose view anyone perceived as critical of Islam deserved death.

The paradox of tolerating the intolerant is a genuine dilemma for liberal democracies. How do you address it? Do you expel Muslims and ban Muslim immigration, as rising nationalist, nativist, and racist parties in Europe demand? That, of course, would simply be to abjure one’s status as a liberal democracy. This is why there has been so much outrage over Donald Trump’s various proposed bans on immigration from Muslim countries. However, inevitably some Muslim immigrants (and others, of course) will have illiberal convictions, or become radicalized once in the country.

BTW, the idea that, in general, Muslim immigrants are a uniquely intolerant group is just not true:

In fact, as the linked article notes, American Muslims are more tolerant of gays than American evangelical Christians. Perhaps, then, the best way to indicate the paradox of liberal democracy is to note that the U.S. not only tolerates, but elects to high office, fundamentalist Christians of theocratic leanings.

This paradox of liberal democracy also raises questions for the very concept of secularism. Secularism has presented itself as a neutral arbiter in the conflict of religious traditions. The position of a secular government is supposed to be one of strict neutrality between various religions, favoring none and permitting the free exercise of each. Religious groups have often attacked secularism, claiming that it is not neutral, and that, in fact it does establish a religion, the “religion of secular humanism.” It allegedly does this, for instance, by permitting the teaching of evolution in public schools while not permitting creationist textbooks. At a deeper level, how can secularism be neutral when confronted with religious practices that undermine neutrality and tend towards hegemony?

The more superficial of the above charges is easily rebutted. Teaching evolution instead of creationism in the public schools no more imposes a secular humanist “religion” than teaching round-earth rather than flat-earth geography. Schools have a responsibility to teach scientific fact as such, oblivious to the grinding of ideological axes or the grinding teeth of offended ideologues.

The deeper-level question must be answered straightforwardly: As a tenet of liberal democracy, secularism is not and cannot be neutral with respect to some religious practices. Rather, it must oppose, and in fact forbid, those practices that are in direct contradiction with the principles of liberal democracy. Thus, it is an outrage and should be forbidden when public school administrators allow fundamentalist groups onto campus and give them freedom to aggressively proselytize students. What part of “public” do those administrators not understand? Public spaces and facilities belong to all the people, and, as such, are not to be used to promote sectarian causes. These fundamentalist groups will no doubt object that, like the Krishnas, such proselytizing is an essential aspect of their faith. Tough.

So, secular liberal democracies are not and cannot be neutral with respect to all religious practices, but must actively oppose some, namely those at variance with the principles of liberal democracy. Religious groups might complain, but really their complaints have no substance. You do not oppress people by forbidding them to oppress, nor do you silence people by forbidding them to silence people. You do not curtail someone’s freedom by keeping him from curtailing someone’s freedom. You do not display bigotry against bigots by not allowing them to act out their bigotry, not even when the bigots invoke “religious freedom” as their excuse.