I attended Orthodox Divine Liturgy yesterday at the Russian Orthodox Church of St. Nicholas, about a 20-minute walk from Central Station. The liturgy was mostly in Dutch. The church is a former Franciscan priory church. A parishioner, a Dutch convert, told me that in Holland you are either a Protestant Calvinist, a Catholic Calvinist, or an atheist Calvinist. He was pretty sure that most of the (tiny) Orthodox minority were Calvinists, too.
I wish your headline were true. It seems to me that most Americans — Protestants, Catholics and atheists — are semi-Pelagians.