You can legitimately try through government force to avoid some of the grosser evils. Shedding of blood is among them. The pattern the Lord has left for civil government is inherited from the instructions Noah got after the Flood, which left Noah as the father of all mankind to be.
The government does not need to be as strict as “the church” about this in order to do substantial good.
Our present government gives us the conundrum that it wants to be part of just about any action. Therefore not to be anti heroin would be to be pro heroin... you can bet Uncle Sam would love the taxes to be had. That’s almost as bad. Laissez-faire outside of the Noahide imperatives is not in his playbook any more.
If on the other hand one justifies the war on drugs because the Bible tells me so, then I have serious philosophical differences with the utterer of that argument. If the Old Testament tells us anything it tells us that God's chosen people, even that divinely selected group, spent most of its history either ignoring, willfully breaking, or misinterpreting God's laws. Whatever the source of apostasy, the lesson is clear, if you would impose your version of holy writ on me, I will rebel and I have no doubt you would do the same. Thus we have the option of having a First Amendment society or a 30 Years War. History teaches us that the former is infinitely preferable.
My position is clear, the war on drugs does profound harm, more harm than good to our society in ways we have not even considered and, to a religiously committed man, ways that are eschatologically meaningful because it is lethal to the very core of individual salvation and drives our society ever further from God. The law provides no salvation to the wicked, no guarantee to the law-abiding.
So the government is "pro-" anything it taxes? Does this "pro-" position manifest itself in any way other than the collection of tax?