Immediately after the terror bombing of a busload of Israeli youth in Burgas, Bulgaria, both Israeli Prime Minister Benjamin Netanyahu and a "senior U.S. official" expressed certainty about Iran's responsibility. Since then, the White House has backed away from that position, after Bulgarian investigators warned against that assumption before the investigation is complete.
Similary, it is generally assumed that Iran and Hezbollah were responsible for the terrorist bombing of a Jewish community center in Buenos Aires on July 18, 1994, because US and Israeli officials, journalists and commentators have repeated that conclusion so often. It was the first reference made by those who were most eager to blame the Burgas bombing on Iran, such as Matthew Levitt and Jeffrey Goldberg.
But that terrorist bombing 18 years ago was not what it has come to appear by the constant drip of unsubstantiated journalistic and political references to it. The identification of that bombing as an Iranian operation should be regarded as a cautionary tale about the consequences of politics determining the results of a terrorist investigation.
Source and full piece: Gareth Porter, Lobelog, 22 July 2012