Once again. I sat on a Federal Grand Jury for a year. I have seen lots of citizens who did harm brought down by these money laundering laws.
Perhaps (though you did not serve on a petit jury, and may not know what became of those you indicted -- and therefore cannot be certain of their guilt).
I have no doubt that police states can be more effective at suppression of unsanctioned crime. The point is, that if the cost is the imposition of governmental terror, the price is too high.
The end does not justify the means. The fact that police state tactics work is interesting, but is not proof that naked utilitarianism deserves a place in a free republic.