In this case, Laetare is a reminder of why we're in Lent: the Lord's resurrection is nearly here. It is a reminder in a time of sacrifice that His sacrifice wins out in the end. It is a reward for passing the halfway point and either enjoying our triumph thus far or setting us back on course.
There are more reasons to rejoice. Despite what the evening news might say, our world is a pretty fantastic place. True, it would be nice if more people could enjoy what our world currently has to offer, but more and more people are. Trust me, as a student and teacher of history, I know of no other time in the world that so many people have had such freedoms, such magic as our current technology, such long lives, and such peace.
The world has long been a violent place, and people have taken advantage of one another since the beginning of time, but those who commit violence and those who take advantage are finding less and less space to live. We live in an age of marvels, and I believe that it will only get better. Look at the great things in your life and realize the underlying truth. We have lives worth celebrating.
Laetare!