Its corollary would probably be "there is nothing to fear but fear itself."
There is a lot of fuss in the media over the arrests of alleged terrorists in Canada, as explained by Dr. Dawg. Worse, the fuss is generally of the fear-mongering variety.
Plenty of people have malicious and murderous intent, and they're not limited to any easily-identifiable "group". Looking at Statistics Canada (while we still can... but that's another subject), the number of homicides in Canada ranged from a low of 594 (in 2007) to 663 (in 2005). In 2009, there were 610 homicides and 806 attempted murders.
There were also 443284 violent Criminal Code violations in total. As it turns out, a lot of people just happen to be malicious jerks (to put it in the mildest terms).
Terrorism is indeed frightening in its concept. Strangers killing other strangers en masse at random and isolated points in time gives terrorism an air of uncertainty, and people naturally fear the unknown. From a statistical standpoint, though, terrorism just isn't a threat that should be on normal people's minds. Major incidents such as the bombing of Air India Flight 182 or September 11, 2001 tend to be the result of series of unfortunate events (i.e. intelligence and law enforcement simultaneously messing up repeatedly) that just are highly unlikely.
The arrests of three alleged terrorists doesn't change anything. The death toll from terrorism on Canadian soil since 9/11 remains 0. Besides, the accused are innocent until proven guilty.
Premature finger-pointing and paranoia only fuels fear and, eventually, hatred. That's not the way to live, and it's not the future that the majority of us want to create.
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"The Drumhead" is a fourth-season "Star Trek: The Next Generation" episode (original air date of April 29, 1991) that is probably brought up a lot in these overly-paranoid times for its prescience, and it really needs to be brought up again. It was probably written with McCarthyism in mind, which means it's not actually prescient. Its relevance is more likely an indication that our society has not learned from history and is now doomed to repeat it (to paraphrase George Santayana).
In summary, a Klingon spy working for the Romulans sends classified schematics of the Enterprise's warp core to the Romulan intelligence agency (the Tal Shiar). Shortly afterward, an explosion damages the warp core but luckily does not lead to the ship's destruction. After the spy is found not to be the cause of the explosion, an external investigator (a Star Trek cliché - a misguided Admiral) starts to suspect a larger Romulan conspiracy within Starfleet itself and begins interrogating a crew member with Romulan ancestry. It's got to be the Romulan crew member, right? (The answer should be obvious, but of course it's not.)
This episode really needs to be watched to be fully appreciated, in my humble opinion anyway.
Worf: Sir, the Federation does have enemies! We must seek them out!
Picard: Oh, yes. That's how it starts, but the road from legitimate suspicion to rampant paranoia is very much shorter than we think. Something is wrong here, Mr. Worf. I don't like what we have become!
Being an episodic series, what they've become is reverted to the norm at the end of the episode. In real life, though, repairing damage done is not easy. It's just best not to go down that path.
Peace and long life.
