Hi,
I believe that your Roman comparison does not help your argument, in fact, just the opposite, due largely to the fact that the Roman example is actually an example that, if anything, shows the Triumph of Christianity in history. Within what, 2 or 3 centuries Christians went from being a small, persecuted class to the the only sanctioned religion in the empire. There are other prime examples of the same, such as the positive moral changes that occurred in England under John Wesley and some of his contemporaries, and most importantly, the formation and establishment of the only nation in the history of the world that came any where close to having a social, political, and religious system conducive to true peace, liberty, and prosperity----in which Biblical principles literally saturated every level of society; that is, early America.
Yes, yes, there are those who perpetuate lies about early America, claiming that it was inundated with various evils. But they are just exaggerations and/or lies perpetuated by the ignorant, the delusional, and/or the wicked.