Dare I say that their greatest weakness is that they depend on themselves or Satan? If we depend on God, how can we lose?
Of course if we are in the End Times, then Satan will seem to win temporarily. We know how that turns out, too.
Still, Sun Tzu's wisdom should be followed.... failure to prepare is preparing for failure
This is similar to a statement Obama made when he was sworn into office - our security is rooted in the justness of our cause. In fact, our security has nothing much to do with the justness of our cause.
Plenty of just people have suffered wholesale damage and destruction in the past. They were no more secure because of their just cause.
Similarly, plenty of people have had faith in God and suffered wholesale damage and destruction. They depended on God, and lost.
I'm just sayin'.