I had a short conversation with my mother over the phone a few days ago where for some reason the Roman Empire came up, and she said she didn't like the Romans. Knowing her, I knew it was because modern American televangilism has taught her to hate catholics (as opposed to other reasons to hate Rome, like the whole empire built on slavery and constant war thing), so I mentioned that without the Roman Empire, Jesus the man wouldn't have ever existed. We didn't talk much longer, she just replied with "You don't know that!".
Which brings up an interesting question I think, which is how differently things would've turned out with only incredibly small differences in history. Obviously if Rome had never taken Judea, like if they lost one of the Punic wars or something, then that would be such a huge change that the individuals born in that province would all be (at least genetically) much different, even ignoring that there would be little reason for an apocalyptic Jewish sect to gain any popularity. But even if things had turned out largely the same, and whoever Jesus' father was had spent an extra two seconds tying his sandals on his way to see the mother whenever he was conceived, I think it would be highly unlikely for the resulting Jesus to be genetically similar enough to our reality's Jesus for Christianity to have the religion ever form around him, or experience enough success to move out of Judea into the Empire. The effects of a different wayward spermlette's genetic contribution compounded over a lifetime would be huge, and his life would've likely been as obscure and unmemorable as everyone else who's lived and died without accidentally starting a world religion.
That's why I think if Christians are going to look for miracles with any kind of rationality, it should be a miracle of statistics and unlikelihoods, only acceptable with a blind faith in fate among what we now understand is an incredibly random and volatile reality. But if they've gotten that far, the growing burden of doubt from the countless other contradictions should already be enough to discard it.