The legalization of Pot-3

Although I am thinking way ahead in this case but how the legalization of Pot impacts the daily life of people. Would they be allowed to keep it in their car and what is the limit like that in alcohol would trigger the Driving while under the influence laws. Would someone be allowed to bring marijuana to work and smoke during the work hours and how are you going to hire somebody who may have marijuana in his/her system because it may be legal but the company’s policy states otherwise. Would there be age limit to who can buy it and would it be allowed or disallowed in public places. How are you going to explain to your kids that a drug which was illegal not in the distant past is now legal and how are you going to say no to it when your kids may say that it is what their friends are doing and is perfectly legal (and supposedly harmless). And where does it all end? Do we then graduate to other drugs like cocaine and heroin and declare them legal too. I have all these questions which may or may not arise while discussing this legalization because for now most of them seem farfetched but there is always a possibility that if the President of the United States have started to somewhat support it ( I am not saying that he supports it now but in the future) then where to do take a stand on illegal drugs or do we ever take a stand on anything then.