Why is Dearborn Michigan overrun with Muslims?

This is america. Why is it so hard for people to understand the expression "When in rome do as romans" If you want to wear a burka, etc then do it in your homeland. This is the USA - A christian nation - if u do not like it, then the same way you got here can return you home. This country was founded on Christian religion. Just look at our money and our founding fathers.