Nicholas Kristof recently despaired about the academy’s lack of engagement with foreign policy–yet academics might also lament the opposite.

I’m referring to the widespread assertion of a familiar trope, which after the crisis in Crimea, is once again blazing its way across op-ed pages: the idea that breaking promises/backing down/displaying restraint in one realm or region will embolden adversaries elsewhere. (Daryl G. Press and I wrote about this when it last reared its ugly head in debates over US intervention in Syria. Press is my Dartmouth colleague and, full disclosure, my husband.)

Analysts are absolutely correct that a country’s credibility is vital: without it, its threats or promises won’t be believed. Yet there is a great deal of confusion about what exactly causes credibility. Social scientists have investigated this question: Press, in his book Calculating Credibility tested a “past actions” theory against a “power and interests” theory.

Namely, does a country’s credibility depend on its past behavior, or on its military power and interests in the realm in question? In other words, will Beijing say, “Obama won’t defend Japan because he didn’t bomb Syria”; or will it say, “The U.S. 7th Fleet could sink our navy, and we know the US has a strong interest in coming to Japan’s aid”?

In their research, Press, Jonathan Mercer, and other scholars found overwhelming evidence that in their decision-making, leaders ignore an adversary’s past actions and instead think about the military power that their adversary wields to carry out its threats, and the interest it has in wielding it.

Yet the reputation trope endures: from the Korean War, to Vietnam, to Syria, and to wherever the hawks will seek to involve the U.S. military next. Sometimes, to be sure, hawks might give us sound reasons to intervene. But make no mistake, reputation isn’t one of them.