It is a cylcle implemented by the U.S. Government to control the weaker people in our society.
The U.S. Government controls 100% of the drug trade in this country, and they also control who free money is distributed to. So, if you are a drug addict on welfare, the Government controls the drugs that you are addicted to, and also control how much money you have. This puts them in total and complete control of your entire life. You are nothing more than a puppet of the Government, and in no way threaten the absolute power sought after by our communist leaders.
If the Government actually tried to deter people from doing drugs, or disqualified people from welfare benefits because of drug use, it would directly affect the power structure that they want in our Government.
By making it mandatory to take a drug test in order to hold a job, the Government strengthens it's hold on the people. If you can't pass a drug test, you can't have a job, and you go on welfare. Thus, putting you in the cycle of total Government contol.