Letter Diplomacy

So I read an interesting story yesterday that illustrates just how complex diplomacy can be.

Apparently during a trip to Israel, Senator John Kerry (D-Mass) toured Gaza and an official from UNRWA gave him a letter that addressed to President Obama along with other documents. Senator Kerry learned later from news reports that it was from Hamas. The letter is now with the consulate in Jerusalem where they will decide what action to take.

According to news outlets, U.S. officials are furious with the UN for passing this letter along. This letter could cause diplomatic complications for the U.S who does not recognize Hamas.
From Fox News:
"A potential concern was whether such a letter would violate the United States' policy toward Hamas. Obama has said his administration will not engage in diplomatic talks with Hamas unless the group renounces terrorism and affirms Israel's right to exist."

So what should the US do? If they ignore the letter now that the press knows who it is from will that create a backlash? Is it better that the President receive the letter and would it perhaps open up some good will and avenues to peace?

Foreign Policy magazine's blog had some good thoughts on this story as well.