Nas Shares Thoughts of 9/11 for Tribute PSA — Watch

This month marks the 10-year anniversary of 9/11, a day that changed how Americans viewed one another, how they traveled and how safe they felt in their own country. Though the day was marked as a tragedy, it caused a nation to unite under extreme duress. In a new campaign titled 'I Will: Join the 9/11 Tribute Movement,' rapper Nas teams up with the likes of new G-Unit signee Pauly D and Lady Gaga, among other celebrities, to share their memories of that fateful day.

During the PSAs, which were created by Viacom to encourage Americans to remember the brave men and women who put their lives on the line to save others as well as volunteer and donate to worthy causes, the famous faces ask the same question: "What will you do?"

"No one was ready for 9/11 when it happened," Queens native Nas admits in the 30-second clip, which will air across all Viacom channels. "I will remember the people that we lost."