Tolerance

Tolerance.
Great word, isn't it?
What exactly does tolerance mean? The capacity for or the practice of recognizing and respecting the beliefs or practices of others, according to Dictionary.com, at least as the first definition.
Seems to me there's something missing from that definition... the ability to discern between that which can and should be tolerated and that which cannot and should not be tolerated.
* I can and should be tolerant of the religious practices of a Hindu family that lives nearby. I cannot and should not be tolerant of the drug dealer who occasionally sets up shop a couple of miles down the road.
* I can and should be tolerant of the law-abiding family of a different ethnic background. I cannot and should not be tolerant of those who would break the law with impunity.
Tolerance, to me, requires a certain standard that should not be violated. Perhaps it's nothing more than common decency... and those who choose to flaunt that common decency should not be tolerated.
Tolerance therefore means I can accept those of any persuasion who comport themselves responsibly. When their behavior becomes irresponsible, I no longer consider myself under order to tolerate that behavior.
There are other definitions for the word tolerance, according to Dictionary.com.
The last seems of particular import these days, in the wake of London:
The ability of an organism to resist or survive infection by a parasitic or pathogenic organism.
Can our civilization resist and survive infection by the pathogenic organism that is the Islamic extremist movement?
Sadly, the answer, thanks to the likes of the hard left, is not certain.