Editing Deterrence

[[File:TwoIslands.jpg|thumb|right|250px|Pure Deterrence]]{{topquote|But the whole point of the doomsday device is lost IF YOU KEEP IT A SECRET!  '''WHY DIDN'T YOU TELL THE WORLD, 'EH?!'''|Doctor Strangelove}}

Deterrence is the art of producing, in the mind of a potential or actual adversary, the fear of consequence for initiating conflict.  It is a subject which comes up frequently in game theory, psychology, and military science.  

Central to the concept of deterrence is that the deterrent must be ''credible'', that is, that adversary must perceive and acknowledge it as a likely and undesirable consequence.  As Fyodor Dostoevsky observed, it is the certainty of consequence, more than the severity, which deters.  Having the means to blow an opponent up doesn't make for credible deterrence if the opponent doesn't believe you'll actually do it.

One of the simplest examples of deterrence in /TG comes from Magic the Gathering: the two untapped islands.  Blue decks in Magic are typically built around ''Counterspell'', a spell which is a hard negation of almost any card another player could cast.  It requires two blue mana to cast, so invariably a player playing blue will generally play to leave two islands untapped in order to use it.  The mere act of having two blue mana untapped implies that the blue player has the potential ability to negate a cast, which thus impacts the opponent's strategy (even if blue is bluffing and doesn't actually have a ''Counterspell'' in hand).