China had such colossal difficulty because it wasn’t Christian. Actually, America isn’t very Christian now either.
I think Chinese philosophy held China back technologically, (And thus made them subject to the dictates of English Guns) but I think what made Opium addiction such a devastating factor in China's history is the fact that the substance is physiologically addictive to humans.
But you touch on a point that I have been pondering for some years; The Role of Christianity in making this nation great. I've read quite a few articles (Starting with De Tocqueville) asserting that it is our Christianity which made us great, and i'm beginning to think it is indispensable to a functioning society.
I ran across this article some months back, and I noticed this one today.
I am coming around to the idea that Christianity (or something very like it.) is a requirement for a functional society. People do not realize how it affects social interaction throughout the whole system. Now that it is in decline I suspect society is going to get a lot more vicious.