Aspiring Wonks: Time once again to whet your appetite by dipping into a classic text waiting for you online or at the library – one that applies to the P-5+ 1 negotiations with Iran. These passages are from the first chapter of Nobel Laureate Thomas C. Schelling’s Arms and Influence (Yale University Press, 1966).

“Diplomacy is bargaining; it seeks outcomes that, though not ideal for either party, are better for both than some of the alternatives. In diplomacy each somewhat controls what the other wants, and can get more by compromise, exchange, or collaboration than by taking things in his own hands and ignoring the other’s wishes… Whether or not there is a basis for trust and goodwill, there must be some common interest, if only in the avoidance of mutual damage, and an awareness of the need to make the other party prefer an outcome acceptable to oneself.”

“The purely ‘military’ or undiplomatic’ recourse to forcible action is concerned with enemy strength, not enemy interests; the coercive use of the power to hurt, though, is the very exploitation of enemy wants and fears.”

“Opposing strengths may cancel each other; pain and grief do not. The willingness to hurt, the credibility of the threat, and the ability to exploit the power to hurt will indeed depend on how much the adversary can hurt in return; but there is little or nothing about an adversary’s pain and grief that directly reduces one’s own… With strength they can dispute objects of value; with sheer violence they can destroy them.

And brute force succeeds when it is used, whereas the power to hurt is most successful when held in reserve. It is the threat of damage, or of more damage to come, that can make someone yield or comply. It is latent violence that can influence someone’s choice… Whether it is sheer terroristic violence … or cool premeditated violence… it is the expectation of more violence that gets the wanted behavior, if the power to hurt can get it at all…”

“The victim has to know what is wanted, and he may have to be assured of what is not wanted. The pain and suffering have to appear contingent on his behavior; it is not alone the threat that is effective – the threat of pain or loss if he fails to comply – but the corresponding assurance, possibly an implicit one, that he can avoid the pain or loss if he does comply. The prospect of certain death may stun him, but it gives him no choice.”

Michael Krepon is Co-Founder of the Stimson Center. This piece originally ran in Arms Control Wonk on June 23, 2015.