Popstar Justin Timberlake was largely the reason actress Mila Kunis accepted an invitation to attend an upcoming Marine Corps Ball — but Cpl. Kelsey DeSantis was the reason Timberlake found himself moved almost to tears at a similar event Saturday night, a night the celebrity writes “changed [his] life.”

After Timberlake publicly urged his Friends with Benefits costar Kunis to say “yes” to the request she received from a serviceman, DeSantis invited Timberlake — via YouTube — to the Nov. 12 Instructor Battalion Marine Corps Ball in Richmond, Va.

“You want to call out my girl Mila?” De Santis asked in a video. “Well, I’m going to call you out and ask you to come to the Marine Corps ball with me on Nov. 12.”

Timberlake accepted and, Saturday night, he kept his promise.

“I knew I would have an evening that I wouldn’t forget… Something I could tell my friends about,” Timberlake wrote the next day. “What I didn’t know was how moved I would be by the whole experience.”

The GQ favorite has always been a vocal supporter of the armed forces — but his glimpse into the camaraderie and closeness of the Marine Corps taught him he’ll never fully understand just what men and women in uniform endure for us — and also that he can never appreciate them enough.

A video tribute to the Marines particularly took Timberlake by surprise:

While this tribute was playing, you could hear a pin drop. It was a surreal moment to be in that room with so many of our great Marines who have such a different type of connection to those stories. One that we who don’t serve will NEVER understand. It was familial. It was like they were listening to their own blood brothers. I glanced around the room at young men and women, spouses and soldiers… At kids way beyond their years, really… All so deeply entwined. Not just by battle, even though we who have never endured anything remotely close to those experiences and have NO position to comment on… But, by having such life changing experiences through them and to not ever waver in their love and respect for our homeland. That’s what I saw. A faith in us that has been tested time and time again. And, through it all, NEVER a drop of doubt. …

The night inspired Timberlake to call on his family, friends and fans to separate their views of war from support for the troops and to intentionally thank those who serve the cause of freedom worldwide.

We all have our own individual views on war… But, doesn’t that speak to just another thing that makes this country so special?? The fact that we can all wake up every morning and BE individual with a pure sense of freedom..? But, one thing that can’t be argued is that it’s because of the people who VOLUNTEER their lives to make sure that it’s protected at all times. And, like I said before, doing so while asking for nothing in return…

To people like me who get to benefit from this type of person… One with character and courage. With strength and bravery. With humility and honor… I say: Send your thanks. Do it however you can. Write a letter, type an email… Hell, buy ’em a beer next time you run into someone from our Armed Forces in a bar. When they say thank you for that drink that cost you 3 bucks, they’ll mean it. They won’t take it for granted and, they won’t forget it.

This phenomenon of inviting celebrities to personally experience some element of American life they wouldn’t otherwise encounter — whether a Marine Corps Ball or a Tea Party rally — seems a healthy development to me, a way of bridging the disconnect. Reading Timberlake’s reaction to this weekend’s event really makes me hope it continues.