First of all, I have absolute zilch knowledge on drugs, law and
whatsoever. But here's my 2 cents worth.
Singapore & United States of America.
There are bound to have differences in the way these 2 countries
are being governed. Simply because they are in 2 different
environments. The environment and the physicality of the country
determine how it is being governed. As mentioned by a fellow
forumner, Singapore's greatest resource is its people.
Alcohol & Smoking VS Marijuana.
As mentioned by fellow forumners, despite alcohol and smoking
having lots of defective effects on the human body, it is not
banned here, perhaps because of it is "socially acceptable".
Apparently, yeah. Probably. The society decides for itself. In the
current society, smoking is probably still socially acceptable.
Marijuana? If the society does not approve of it, so be it. Move on
to another society that does. As argued, smoking is just as bad as
marijuana but hey, the society's mindset takes time to
adjust.
Some of you are probably right. Smoking should be totally banned as
well. The government are probably not banning it due to economical,
policital reasons. But you see, steps are taken to reduce smoking
in Singapore. The gross pictures, the no-smoking areas. Why not
just implement a total ban? That will be economical suicide. Just
because smoking is not ban, it is not a reason for marijuana to be
un-ban. 2 wrongs definitely do not make 2 rights.\
You see, to legalise marijuana now is to bring MORE detrimental to
the society in terms of health. To illegalise alcohol and smoking
now would also bring MORE detrimental to the society in various
aspects.
The Topic.
What exactly is the argument here?
1) The fact that 2 children are pleading for their dad which should
lead to the law making an exception?
2) Or the law itself being flawed?
3) Or down with capital punishment?
1) No arguments for the 1st. The law is the law. Many forumners
have point out this point pretty well so no repeats.
2) Flawed law? Can be argued.
3) Yeah, down with capital punishment.
Regarding that black slavery thingie, you can't really use it as a
comparison. It is as though you are trying to say, banning
marijuana is an injustice done to the society. And even if alcohol
and smoking is not being banned, it doesn't make marijuana any
lesser evil.
Eh wait, are you arguing for marijuana to be made legal here in
Singapore?
Pardon my bad english. 
