Right. So just being 'ahle-kitab' is not sufficient. One has to accept Allah as God and Mohammad as his last messenger. That means the person has to change his belief. This falsifies your statement that Muslims and Christians can intermarry.
Are you referring to Christian men, or Christian women?
I know of Muslim women who have married Christian men. They declared that they accepted Islam ie. they bore witness that they believed that it was true
It doesn't mean that they pray 5 times a day or even go to the mosque on a friday
..it depends on the family of the bride, really
Oh .. and somebody who witnesses Islam to be true does not necessarily make their previous faith null & void.
A Muslim believes in Jesus, Moses, Abraham, peace be with them. The "son of God" thing is not really understood by a lot of Christians, in any case.
Furthermore, some Christian denominations already believe in the unity of God