Brad Paisley is not one to back down from a challenge, especially if the winning prize is a free drink.

This time last year, Paisley was asked to hop on Air Force One with the president and head over to Afghanistan to play and thank the troops before Memorial Day. After successfully completing that top secret mission, he received a military challenge coin, a token that could potentially earn him a free drink at any bar for life — somewhat ironic, since the star is actually a teetotaler.

At a roundtable interview last week, Paisley told Taste of Country and several other media outlets exactly how that works and what it all means to him.

"One of my favorite things I have is a military coin," Paisley proudly says.

There are military challenge coins that every rank of officer has with their actual rank on it, he explains. The way it works is if you're at a bar, you can set the coin on the bar next to another military member, and that acts as a challenge. If you outrank the person you challenge, or they don't have their coin on them, they have to buy you a drink. But if their ranking is higher than your own, it is your responsibility to buy the next round.

"I've got everything from the coin from the commander of Air Force One to the president, which wins any bar," Paisley shares. "But the interesting thing is, I have a coin from the aide that carries the brief case that carries the nuclear codes and all that. He was a great guy, one of the favorites from my trip."

The moral of the story is that Paisley met the guy who holds the most top secret information in the world — and we can't be the only ones concerned about that.

Paisley is staying clear of presidential missions for the time being, so you can catch him at LP Field in Nashville during June at the CMA Music Festival and when he opens for the Rolling Stones June 17, or on his Crushin' It tour with Justin Moore and Mickey Guyton.

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