I like this phrase: "I tell you these things... lest the wickedness of men reveal these things unto you by their wickedness" which I take to mean that rather than having the saints learn of the wickedness of men by experiencing it firsthand, the Lord is warning them so they can avoid it.D&C 38
29 Ye hear of wars in far countries, and you say that there will soon be great wars in far countries, but ye know not the hearts of men in your own land.
30 I tell you these things because of your prayers; wherefore, treasure up wisdom in your bosoms, lest the wickedness of men reveal these things unto you by their wickedness, in a manner which shall speak in your ears with a voice louder than that which shall shake the earth; but if ye are prepared ye shall not fear.
I think that some people can learn through study or warnings or inspiration, but others just won't believe it untill they see it or it happens to them.
I think there is a dangerous erosion of liberties going on, but some people just won't get it until a SWAT team in Darth Vader suits kick down their door. Some people just won't believe that there is a problem with depleted uranium with the troops in the middle east until their cousing gets cancer. For some, it's just not a real concern until it directly affects them or is directly observable by them.