Japan is one of the most authoritarian countries in the world with respect to law enforcement.
There is next to zero private ownership of firearms. The police can hold anyone for questioning for an indefinite period, without any probable cause or even suspicion. There are no rights against unreasonable search and seizure. Americans would not tolerate such a police state.
Yet even that rigid law enforcement cannot stop "crazy" or "evil". Q.E.D.
Yet.
In the last 100 years liberty has eroded significantly and the rate of erosion has accelerated since FDR.
When I think of the impositions put on private property by The Clean Water Act and the advent of No Knock Raids, I wonder if the Bill of Rights really matters any more.
And now with Obama Care the IRS can track your bank accounts and medical records.
Then we have the FISA Secret Warrants; they can search your home with out ever telling you and if you discover that your home was searched you are by law forbidden to tell anyone. We the people are supposed to be comforted by the fact that these warrants are approved by special judges. Oh I am very comforted that pretty much all of the warrant request are approved by these judges.
Our rights are vanishing like the morning dew and we had better start fighting those that want our rights to evaporate.