20% of Americans are not Christian

These are some very interesting statistics:

In their American Religious Identification Survey, researchers at the City University of New York discovered that from 1990 to 2001, the number of people in the United States ,who have a religion other than Christianity increased from 5.8 million to 8.7 million. Such a number, albeit still small, reflects a sizeable minority, which practically did not exist years ago.

Much more significant than the increase in non-Christians is the increase of people who identify as atheist and agnostic. Non-religious people were usually a very small and intellectual minority in the first half of the twentieth century. Today, they compose about fourteen percent of the American population, as pointed out in the aforementioned study, after having more than doubled in size from fourteen million people to practically thirty million people between 1990 and 2001. Together with non-Christians, they compose practically twenty percent of the American population – a percentage that is growing, according to the study.
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When the religious spectrum was monolithic, public manifestations of the majority faith were not bothersome to most people. Now, in a much more varied religious climate, it seems logical not to encourage any particular brand of faith in a public space. Thus, the much-criticized secularization of public places is actually an important step toward protecting religious freedom, and creating a more diverse and equaitalbe society. It helps reinforce the values enshrined in the U. S. Constitution and respects people's rights to choose whether to have a faith or be part of a religious institution. It also protects newer churches and religious groups from state-sponsored propaganda of older ones. And, as long as religions have the right to worship in their houses of prayer and act according to their beliefs, their rights are protected. The ongoing changes are definitely for the common good.

I completely agree.