Not to rain on your parade, have you considered how long ago David uttered that prayer and how many millions of people have read and repeated it since? You've observed yourself that things are as bad if not worse than when David first made that prayer. Maybe it's time for something other than prayer? it doesn't seem to have done David (or anyone else, for that matter) much good. Instead of wishing and hoping, have you considered actually getting your hands dirty and doing something about the state of the world and humankind?

Just a thought.