DM are here since some years actually. Will they always be there? What's in your opinion the biggest threat for those markets? Decrypting tor? Lack of people to run them because it's dangerous? Loss of interest because of scamming and going back to the old style street deals? Impossibility to use bitcoin anymore? We want to know the main reason why they could stop in the future and, possibily, when.
Improved methods of detection and confiscation of illicit goods in mail. Both domestic and international.