Indian American marriages
It is good you brought up the question of Hindu - Christian or Indian American marriages. It is true that far more Indian Hindu and Amercian Christian marriages are taking place than the Hindu Muslim but I view them slightly differently from the Hindu Muslim marriages.
Indian American marriages -- I look upon as a natural phenomenon which a liberal and educated immigrant community will naturally go through and in the long run I see it as a positive sign. It is not forced upon by either party.
If in India we expect the invading Muslim hordes to have become Indian and to have taken Indian identity -- I in all honesty cannot repeat the same and justify it. In the long run we and our children should get assimilated in the American society.
Most Americans who marry a Hindu don't insist on change of religion. There is much give and take. If the progeny is brought up as Christian -- it is in my observation more the submission of the Hindu parent than the demand of the American parent. Mostly it is immaterial whether the Indian parent is male or female. Catholics may be an exception -- they do insist that the children be brought up as Catholics -- mostly but not all do. They do not insist on the person getting married must convert -- this is almost a must for most getting married to a Muslim.
In a American Indian marriage the Hindu female lives a free life while to the contrary in Muslim Hindu marriage, almost without exception the Hindu party must change his/her religion.
If a Muslim marries even an American, change of faith in most cases is a must, at least for the time of marriage ceremony.
Yes, there are fanatic Christians around but all said and done, most Americans are not all that hung up on Christianity. If a Hindu wants to follow her or his beliefs, most Americans don't come in his/her way. Many Americans who have married Indians are very keen on learning about Hinduism and a few of them I have to be more Hindu than the Hindu marrying them.
Most Americans today are as liberal in social attitudes as Hindus are. Apart from Christianity, there is a new American culture developing - like many Hindus are Hindu in name and just plain simple folks for all practical purposes -- I believe most Americans are also like that. Their main concern is make a living , have a good time and live a prosperous life. Not many Americans believe in the Bible or follow it to any extent.
I personally see no objection to two marriage ceremonies -- this, as far as, I can see only goes to show the flexibility of the American partner. I believe it is a positive sign and good for social integration.