Second, Rouhani’s objectives are overwhelmingly tactical. Widening Western sanctions are having a real and significant effect on the Iranian economy, from soaring inflation to rising commodity prices. That’s a real challenge to the legitimacy of Iran’s president, who campaigned successfully this summer on a platform of economic renewal. His overtures, then, smack more than a little bit of personal face-saving and domestic politicking.

They also run counter to the plans of others in the Iranian regime. Iran’s powerful Revolutionary Guards, for example, have signaled in no uncertain terms that Rouhani has an exceedingly short leash for his diplomatic overtures, and that any deal with the U.S. won’t entail a “retreat from fundamental rights” to develop a nuclear capability. That suggests that whatever bargain Rouhani is actually empowered to strike with Washington is destined to be decidedly modest in scope — and won’t answer fundamental concerns over the scope and intent of the Iranian regime’s nuclear endeavor.