Today marks 55 years since Julius and Ethel Rosenberg were executed, convicted of "conspiracy to commit treason." The passage of 55 years - and the release of previously-classified documents - haven't yet succeeded in putting this case to rest.

The figure of Ethel remains particularly haunting. The tiny woman, too small for the electric chair to do its gruesome job quickly and effectively. The stoic woman, cast during the trial as unfeeling and unfeminine. The mother, accused by the press and others of selfishly sacrificing her children to the cause of Communism. The wife, held (and killed) by the government in an attempt to force her husband to reveal information. The sister, turned in by her brother. The daughter, whose own mother did not even attend her funeral.

She is a figure who (to me at any rate) radiates power from her small frame. And yet she is also a cipher of sorts - projected upon, reimagined, but not heard in her own voice. In an excellent documentary - Heir to an Execution - made by her granddaughter, Ivy Meeropol, we hear the words of letters she wrote while in prison. But the questions - and longing to know her more - remain.

May her memory be for a blessing.