Over 15 years ago I had a Managua-Miami flight in a B727 and an obnoxious drunk kept pinching my Colombian FA's rear ends when they walked by and FAs said the retired military guy across the aisle said the guy said he had a gun in his bag. I went back, asked the military guy if this was the bag and he said yes. I took it and said he would get it back when he left the airplane. He still wasn't cooperating so had the FAs move everybody in the back five rows forward and made him change his seat.
I put him by the window in the back and I said if you cause one more problem I will land at the nearest airport and have you arrested. He laughed so I said do you know what that airport is? Havana, Cuba. If we land there Castro will kill you tomorrow. He quit smiling and I kept making PAs as we approached Cuba of where Havana was and he didn't move. Once in range of MIA called to have security meet us and he was deported the next day. I know threatening somebodies life is not standard procedure, but it worked. Also nobody else heard me. Sometimes you just have to do whatever works.
Now after 9/11 we can't do that.