America needs to avoid what's happened in Europe. There are three major movements contending with one another across the planet: Secularism, Islam, and Christianity. Africa, for instance, is a chessboard being contended for by Christianity and Islam.
For a few hundred years in Europe, the Enlightenment existed alongside the world of rational faith, and was strengthened by it. Over the past 100 years Europe has cut itself off from its roots, by destroying Christianity on the continent. Instead of a foundation of certainty, conscience, and hope, Europeans have embraced a foundation of UNcertainty-- of a relativism which believes, ultimately, in no real truths or values at all. Not just Christianity has been killed, but a key part of the Enlightenment also.
Christianity was important not simply as a religion. It was part of Europe's cultural and historical identity. When Europeans wiped out Christianity, unwittingly they wiped out part of themselves.
They're left in the situation of Montezuma and the Aztec empire-- certain of nothing, believing in ephemeral unknowable winds of change; existing as a corrupt and tottery edifice waiting to be knocked down. Islamicists know this. Europe is dying demographically and in every other way, because it no longer believes in itself, and so appears unable to stand up against a strong force which does. You don't beat something with nothing. This is the uncomfortable truth but it's not too late to be turned around.