A few myth-conceptions
Cannabis can be addicting - just like alcohol or other drugs, most people who try or use alcohol/cannabis/other drugs do not become addicted - but just because ones personal experience with usage did not lead to them becoming addicted does not mean that therefore a drug isn't addicting. People who are addicted to cannabis have at times due to their addiction given up their freedom for it, lost careers and family over it, and placed their lives and the lives of others in jeopardy due to their continued usage.
Alcoholics Anonymous does not require any belief in God in any traditional sense of the word - in Narcotics Anonymous and in Cocaine Anonymous they even took out the word God and use instead the term "higher power."
If one is really interested in what the 12-step programs are really about - then read the basic texts of the programs - they are readily available as are open meetings that anyone off the street may attend to satisfy their curiosity.
Studies that purport to show recovery rates are generally as reliable as the studies put out by gun control groups and one should read them with an understanding of what they say and don't say. I.E. The chances of an individual staying clean and sober after attending their first 12-step meeting is not very high. However, individuals often do not achieve long-term recovery on their first attempt. An old 12 Step saying is that if an individual is willing to put half the effort into recovery that they did into their addiction then they will get sober.
12 Step programs do not require anyone to do anything - though they do suggest a 12-step program of recovery - they are independent and self-supporting.
Fewer and fewer treatment programs are the old 12 step programs based on AA/NA/CA - while the majority still utilize and encourage 12 step programs and meetings as a part of a long term recovery plan - they do not typically focus treatment primarily on the 12 steps - most focus on helping individuals to address issues related to processing feelings (individual and group therapy - RET rational emotive theory), developing living skills, (anger management, assertiveness, coping styles, stress management, relapse prevention, recreation and leisure, job and education skills, etc...).
A couple of final points -
If one is not addicted it is almost impossible to truly understand it.
If one is in active addiction - they will almost assuredly define addiction so that it does not apply to them. I.E. If one is an alcoholic and one doesn't drink everyday then isn't it obvious that in order to be an alcoholic that one must drink everyday? Of course, most alcoholics don't drink every day. That is called denial and it is a part of the illness that is addiction.
Addiction is a chronic, progressive, incurable illness, characterized by loss of control over ones usage of substances and by denial of ones addiction. It adversely impacts individuals on physiological, psychological, and spiritual levels and that impact/damage happens gradually over a period of time - recovery from addiction is also a process that occurs over time.
There is no simple political solution to the problem of addiction. The legalization or illegalization or Alcohol/Drug use will have little impact on the problem of addiction.