Serious question for Christians, no snark intended. If you were born in, say, Afghanistan you would have been raised Muslim (or Israel and raised Jewish...whatever) and would be just as devout a Muslim as you are a Christian in reality. You would be just as adamant that Islam is the truth and the only correct religion. You'd raise your family Muslim just like you're raising your family Christian now.
But you weren't. You were born in a country where historically the majority happen to believe in Christianity and the Bible instead. The fact that you became a Christian is largely a product of the culture in which you were raised. There's no question about that. That's the reason you believe in the Bible instead of the Koran (or the Torah or whatever). How do you reconcile that?
See Ed, that's why I like you...because you are a genuine dude. Instead of lobbing bombs aimed strictly at the hot button issues you actually bring up a great point.
There is absolutely no doubt that culture plays a huge role. For me personally I did not grow up in a christian home. That came later for me when I dabbled with Christianity when I was very young and then later rejected the idea because of something that my grandmother said to me when I was about 9-10 yars old. She told me that Gid would punish me for all of my sins, so I was like, "f-it, I am a sinful bastard, so I'm about to live it up." I knew there was no way I was going to be a good kid. I was a holy terror that loved just about every perverse thing you could imagine. So I threw my middle finger up at the idea that I needed to be good enough to be accepted. Grandma proved to be poor example of evangelism because she failed to tell me the rest of the story which was there was a dude named Jesus that came to remedy that problem. Later I experimented with some eastern phylosiphes while struggling to make some changes in my life before I became a Christian. That doesn't answer your question...only providing a little background.
The point that you brought up wasn't really addressed for me personally until after the fact. Truthfully I didn't know enough when I converted to have that discussion. I simply desperately felt the need for a savior at the time. During the last 20 or so years I've had to hash out many issues and questions. While I was going to bible college and graduate school at Fuller Theological Seminary tons of these things came up. We examined all of the major religions and I became very interested in those topics. Since my conversion I've been one who studies the bible and history concerning religion. I'm certainly not saying I am an expert but I have dedicated myself to learning over along period of time.
Logically speaking, I probably would be Muslim right now if I was born in a Muslim country. Culture has a powerful impact on these things. How I reconcile it now is pretty simple. I am thankful that I was born where I was. I am thankful for the events of my life that lead me to the truth that I know. It is a pretty big difference when I ask that question vs. you hashing that question out in your mind. I feel firm in my belief structure based on study but that would have not likely have happened if it weren't for culture. I wouldn't say that I continued in my belief with without some pretty intense questioning over a very long period of time. In other words I didn't take grandma Joe or pastor Dingleberry's word for it. I honestly compared and looked into it myself and continued in my choice.