The American Christian-based culture certainly have much great contribution to the world, such as in fellowship, in being neighborly, etc.
However, it also brought along lots of vain and disgusting elements, treating them as principles that even Christians must somehow abide by: such as the need for fame, reputation worship, association with famous people, inability to find reconciliation, easy hatred, political correctness, appreciating men's respect instead of favor from God, etc. All these childishness may signal the end of the American Christianity's short lived glory, if not what Gilbert Tennent feared.
Now in Asia, there are more and more good Christians coming out, the likes of Ahok and many more are signs of the need for prayer in Asia, for God's glory is what matters.