Your review of Christopher Caldwell’s Reflections on the Revolution in Europe: Immigration, Islam, and the West (London: Allen Lane, 2009) grabbed my attention at once when I read that “a surprising number of immigrants proved ‘unmeltable’,” which is a truly delicious term (“A Treacherous Path?” August 29, 2009). Of course, it refers to the American “melting pot,” a felicitous term, as well. Caldwell’s pessimism on Islamic immigration at once finds a solution in the confluence of these terms. Once upon a time, Americans immediately accepted anyone who declared that he or she was an American. Accent was immaterial. That was the other side of the melting pot of old, just like the pronouncement that one was a Muslim at the origin of that faith. Only imagine this attitude in stuck-up Europe of today. Once an immigrant, always an immigrant. Which helps explain the unmeltable ones, as well as Caldwell’s misbegotten pessimism. To wit, melting pots work both ways, or they do not work at all.