I think the USA is following in the footsteps of Europe, a few decades behind. And that doesn't bode well.
BUT I think the diversity of churches here and the historic LACK of state involvement could help here. We're not dealing with a political issue of a state church and church taxes; we don't have the equalization of Christianity with the state denomination of that country. This has always been a country of enormous diversity and choices.
I suspect we'll see a LOT more house churches and a lot fewer traditonal building-on-the-corner churches. Big mega churches will continue but I think the great majority of Christians will be in small fellowships, most not meeting in distinctive buildings at all.
I suspect we'll find far fewer who are active members of some church (even a house church) but the ones who are are more dedicated, more active (I think we're already seeing that rather powerfully). The Voice of the Church may be no less than now, just with fewer and more faithful people.
I think "Lite Christianity" (so popular today) will die. It will be replaced by fellowships that believe something and that belief is what ties them. That and their LOVE for each other.
I think the internet is going to play an increasing role. Denominations may be more about their internet ministry than history. LOTS of Christians will "connect" with a denomiantion via the 'net. For some time, the LCMS was known as "the Church of the Lutheran Hour" because far more Americans knew Lutheranism from that once HUGELY popular radio show than from its congregations; I think something similar is just ahead.
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