The vast majority of Christians, as of 2008, have either forgetten, ignored, or torn this teaching out of their Bibles. Perhaps the most challenging teaching Jesus gave us. Easy enough to love our friends and the good God, but very difficult to even try to love our enemies.
It's anticipated that within the near future, Christians will re-incorporate this principle into their lives.
Questioner: Umm...didn't Jesus teach us "love your enemies"? It says so in Matthew 5:44!
Christian: "Love your enemies"? Oh, I hated that section so I tore the page out of my Bible! LOL! :)