When Barack Obama took the podium before Turkey's parliament in April 2009, in his first overseas trip as president, he delivered a speech that echoed much of the happy talk that has characterized U.S. rhetoric toward Turkey over the past decade. "Turkey is a critical ally. Turkey is an important part of Europe. And Turkey and the United States must stand together -- and work together to overcome the challenges of our time."

U.S. officials have repeated variations of this line since the rise of the ruling Justice and Development Party (AKP) in 2002. When I visited Turkey in March, a well-placed American source made the same point: Sure, the United States was concerned about Turkey's warming relationship with Iran and Syria, and its war of words with Israel -- but those differences paled in comparison with areas where the two countries worked together, such as on Iraq and Afghanistan.

The recent WikiLeaks document dump, however, proves that the U.S. diplomatic corps' concern about Turkey's drift away from the Western alliance runs deeper than it let on publicly. One cable reportedly describes Ahmet Davutoglu, Turkey's foreign minister (and No. 7 on Foreign Policy's 2010 Global Thinkers list), as exerting an "exceptionally dangerous" Islamist influence on Prime Minister Recep Tayyip Erdogan.

And that's just the beginning of it. Davutoglu and other AKP leaders have scant understanding of how their foreign policy will be understood outside of Turkey, because their knowledge is "handicapped... by their Turkey- and Islam-centric vision of how they want the world to operate," according to another cable. The same cable expresses dismay at Erdogan's inability to view Islamist groups as terrorists. The report summarized the prime minister's views thusly:  "Hamas and Hizballah are the result of Western policies gone awry, a response from desperate people -- not truly terrorists."

The leaked cables also show how U.S. views toward the AKP shifted since its early days in power, when it was actively pushing a number of economic and judicial reforms meant to bolster its case for joining the European Union. One document, written in 2004 and signed by then-ambassador Eric Edelman, concludes that Erdogan "is the only partner capable of advancing toward the U.S. vision of a successful, democratic Turkey integrated into Europe."

Even this broadly positive impression, however, contains a few nuggets that the State Department undoubtedly wishes had been kept private. While praising Erdogan as an uncommonly talented politician, it accuses him of "unbridled ambition stemming from the belief God has anointed him to lead Turkey" and "an authoritarian loner streak." Perhaps most embarrassingly, the cable charges the prime minister with harboring "a distrust of women," leading him to exclude them from any prominent role in the AKP.

By 2010, however, U.S. diplomats' frustration with Turkey's government had escalated. A cable written in January by Edelman's successor James Jeffrey condemns Turkish leaders' "special yen for destructive drama and rhetoric," and says that the government possessed "Rolls Royce ambitions but Rover resources," which led to it throw its supports behind "underdogs" such as Hamas leader Khaled Meshaal or Iranian President Mahmoud Ahmadinejad.

The problems are not merely in the realm of style and rhetoric. The cable laments Turkey's habit of presenting itself as the Islamic conscience of NATO, noting that "[e]xtrapolating that behavior into the even more diversity-intolerant EU is a nightmare." In the intervening six years since the 2004 cable, U.S. diplomats tempered their hope for a broad-based strategic partnership with Turkey in favor a "more issue-by-issue approach, and a recognition that Turkey will often go its own way."

Throughout the AKP's transformation of Turkish foreign policy, U.S. diplomats largely expressed their concerns in private. Publicly, their rhetoric was closer to Obama's happy talk to the Turkish parliament -- and Secretary of State Hillary Clinton on Monday largely echoed that line ahead of her meeting with Davutoglu in Washington. State Department officials assumed, no doubt correctly, that heavy-handed ultimatums from Washington would only confirm Turks' beliefs that Washington would never support their newly independent role on the international stage. Now, of course, their careful discretion has been blown apart -- and the U.S.-Turkish relationship could become one of the most prominent casualties of the WikiLeaks' document dump.