Here's a long, but vital essay by George Weigel:

Earlier this year, five days short of the second anniversary of the Madrid bombings, the Zapatero government, which had already legalized marriage between and adoption by same-sex partners and sought to restrict religious education in Spanish schools, announced that the words “father” and “mother” would no longer appear on Spanish birth certificates. Rather, according to the government’s official bulletin, “the expression ‘father’ will be replaced by ‘Progenitor A,’ and ‘mother’ will be replaced by ‘Progenitor B.’” As the chief of the National Civil Registry explained to the Madrid daily ABC, the change would simply bring Spain’s birth certificates into line with Spain’s legislation on marriage and adoption. More acutely, the Irish commentator David Quinn saw in the new regulations “the withdrawal of the state’s recognition of the role of mothers and fathers and the extinction of biology and nature.”

At first blush, the Madrid bombings and the Newspeak of “Progenitor A” and “Progenitor B” might seem connected only by the vagaries of electoral politics: the bombings, aggravating public opinion against a conservative government, led to the installation of a leftist prime minister, who then proceeded to do many of the things that aggressively secularizing governments in Spain have tried to do in the past. In fact, however, the nexus is more complex than that. For the events of the past two years in Spain are a microcosm of the two interrelated culture wars that beset Western Europe today.

The first of these wars—let us, following the example of Spain’s birth certificates, call it “Culture War A”—is a sharper form of the red state/blue state divide in America: a war between the postmodern forces of moral relativism and the defenders of traditional moral conviction. The second—“Culture War B”—is the struggle to define the nature of civil society, the meaning of tolerance and pluralism, and the limits of multiculturalism in an aging Europe whose below-replacement-level fertility rates have opened the door to rapidly growing and assertive Muslim populations.

The aggressors in Culture War A are radical secularists, motivated by what the legal scholar Joseph Weiler has dubbed “Christophobia.” They aim to eliminate the vestiges of Europe’s Judeo-Christian culture from a post-Christian European Union by demanding same-sex marriage in the name of equality, by restricting free speech in the name of civility, and by abrogating core aspects of religious freedom in the name of tolerance. The aggressors in Culture War B are radical and jihadist Muslims who detest the West, who are determined to impose Islamic taboos on Western societies by violent protest and other forms of coercion if necessary, and who see such operations as the first stage toward the Islamification of Europe—or, in the case of what they often refer to as al-Andalus, the restoration of the right order of things, temporarily reversed in 1492 by Ferdinand and Isabella.

The question Europe must face, but which much of Europe seems reluctant to face, is whether the aggressors in Culture War A have not made it exceptionally difficult for the forces of true tolerance and authentic civil society to prevail in Culture War B.