We didn't do anything wrong, but among the lessons learned, given the magnitude of the problems we now face in Afghanistan, a major U.S. force on the ground would convince the world we were in for the long-haul recovery of a country devastated by 21 years of warfare.

We in the United States should be all the more thankful for the freedom and religious tolerance we enjoy. And we should always remember the lessons learned from the Holocaust, in hopes we stay vigilant against such inhumanity now and in the future.

I believe that nothing is more important to our ability to effectively address our present than understanding the lessons learned from those who have come before us.

Despite what Washington thinks or does on this 15th anniversary, we the people will never forget those who perished and the lessons learned on Sept. 11, 2001.

The Army will take its lessons learned. They're excellent at looking into themselves and reflecting on what did we do right, what did we do wrong.

Our brothers and sisters in the trans community, they showed up to every one of our marriage marches when it wasn't necessarily what they needed. So we have to be there for them, use our lessons learned in the marriage fight - how to win when it's difficult, how to change minds that are difficult to change.

One of the lessons learned in the Middle East is to never try to anticipate the other side's moves.

I am big on - even with our whole team - it's always about, well, what were the lessons learned? Something didn't work out? What are the lessons learned? What are the lessons learned?

I do believe in lessons learned. I have learned that you work with gang members and not with gangs; otherwise, you enforce the cohesion of gangs and supply them oxygen.