Ayatollah Ali Khamenei (Office of the Supreme Leader)

On Thursday, The Wall Street Journal reported that President Obama wrote a secret letter to Iran's Supreme Leader Ayatollah Ali Khamenei last month. In it, the president urged that the two countries work together on battling their mutual foe, ISIS, and also reportedly pushed for a long-term deal over Iran's disputed nuclear program. The negotiations over the latter are set to end on November 24 and are reportedly not going well.

The White House, when asked about the letter, did not deny its existence, but also would not comment on it. On Thursday afternoon, White House spokesman Josh Earnest told reporters:

"I'm not in a position to discuss private correspondence between the president and any world leader. I can tell you that the policy that the president and his administration have articulated about Iran remains unchanged."

There are a number of particulars about this revelation that will likely become the subject of opinion pieces in the coming days. One will be the apparent linkage between striking a nuclear deal and the cooperation with Iran in the fight against ISIS. According to The Wall Street Journal, the letter emphasized "any cooperation on Islamic State was largely contingent on Iran reaching a comprehensive agreement."

As Armin Rosen noted, in the past the administration stressed several times that there is no connection "between the nuclear negotiations ... and the host of other matters bearing on relations between the US and Iran."

There's also the matter of priorities. When it comes down to it, the outcome of the slow-burning dispute over Iran's nuclear program is a more pressing matter for both Iran and the United States than the battle against ISIS is. Iran has been hit hard by unprecedented sanctions as a result of its nuclear ambitions, sanctions enacted through American-led efforts. For his part, President Obama has staked much of his foreign policy agenda (and credibility) on a pledge to stop Iran from getting a nuclear weapon.

So why was the letter publicized? As Meir Javedanfar speculated, it makes it more difficult for Iran to walk away from the nuclear negotiations as the aggrieved party. He added that both President Obama and Iran's President Hassan Rouhani stand to gain from the letter: "I believe they both want a deal, and this letter increases pressure on the main obstacles to an agreement inside Iran, namely the hardline Iranian political elite who have been close to Ayatollah Khamenei for many years."