Updated

Signing the new START treaty on April 8 to slash the U.S. and Russian nuclear arsenal, President Obama declared, "I...came to office committed to 'resetting' relations between the United States and Russia, and I know that President Dmitry Medvedev shared that commitment."

Relationships matter. Personal chemistry between Ronald Reagan and Mikhail Gorbachev helped end the Cold War. The connection between George W. Bush and Vladimir Putin was more strained. While at his first meeting with Putin in June 2001, Bush said, "I was able to get a sense of his soul." Many of his aides left office wondering if Bush had seen a mirage.

For Obama, Medvedev might seem a breath of fresh air. While Putin, who now serves as prime minister, works to rehabilitate Stalin, Medvedev castigates Stalinists for the "destruction of their own people" and "millions of ruined lives." And while Putin dispatches police to break up opposition rallies, Medvedev laments that "Democratic institutions have been established and stabilized, but their quality remains far from ideal. Civil society is weak."

It is always dangerous, however, to base policy more upon rhetoric than reality. Here, the Iran experience provides a cautionary tale: In 1997, Iranians defied the establishment to elect Mohammad Khatami as their president. In a sea of dour faces, Khatami was a smiling cleric who promised change. "He is a reformer with an outspoken commitment to civil society, social justice, the rule of law and expanded freedom," wrote Gary Sick, a Carter aide who follows Iran. But in reality, as security forces shuttered newspapers, beat students in the street, and murdered dissidents, Khatami stood aside. He may have been president, but he did not have power.

Six thousand miles away, the Clinton administration also let its optimism cloud its judgment. In his first speech as president, Khatami declared, "We are in favor of a dialogue between civilizations and a détente in our relations with the outside world." Clinton saw opportunity. He had Madeleine Albright, his secretary of state, send a letter seeking engagement. Dialogue floundered, however, when the Islamic Republic made talks conditional on U.S. trade concessions. While former National Security Adviser Brent Scowcroft criticized the Clinton administration's obstinacy, the White House's initial caution, while fleeting, was prudent. Years later, Abdollah Ramezanzadeh, the Khatami government spokesman, explained, "We had one overt policy, which was one of negotiation and confidence building, and a covert policy, which was continuation of the activities." Indeed, when Clinton lulled by lofty dialogue let  his guard down, Tehran exploited it. Behind the talk of dialogue and peace, Iranian engineers and Revolutionary Guardsmen worked to develop Iran's nuclear and missile programs. To engage Khatami was to tilt at windmills. Behind the curtain, Supreme Leader Khamenei called the shots.

In high stakes diplomacy, Obama lacks even Clinton's caution. Whereas Clinton refused Tehran's demands for concessions, Obama has been obsequious, sacrificing military partnerships with Poland and the Czech Republic in the process. Still, while Medvedev may be free to speak, it is not clear he is free to act. Over the past decade, Russia has revitalized its tactical nuclear program and will float a new nuclear submarine next month. Medvedev may be sincere, but his praise for a "verification mechanism [that] has been significantly simplified and [is] much less costly," should raise concern. Medvedev may be president, but it appears Putin and his proxies control Russia's military industries.

As Obama seeks to fulfill his Nobel Prize and realize a nuclear free world, he treats diplomacy as a means of conflict resolution. In both Russia and Iran, however, engagement and agreements are asymmetrical warfare tactics. Liars use the same words as those who tell the truth. Just as Washington pays the price for the Khatami deception a decade ago, historians may view Obama's embrace of Medvedev as a "Mission Accomplished" moment that presaged years of conflict.

Anna Borshchevskaya is a research analyst at the Peterson Institute for International Economics; Michael Rubin is a resident scholar at the American Enterprise Institute.

Fox Forum is on Twitter. Follow us @fxnopinion.