“Unmasking” is the revealing in intelligence reports of the identities of Americans whose communications (or information about whom) have been “incidentally” intercepted during foreign-intelligence-collection operations.

Of course, the fact that a subpoena demanding information is issued does not necessarily mean the information exists. Nevertheless, the issuance of a subpoena implies that the issuer has a good-faith basis to believe it does. On that score, it has previously been reported that the committee’s chairman, Devin Nunes (R., Calif.), has reviewed intelligence reporting and detected instances of unmasking.

Were there to be information indicating that Ms. Power was involved in unmasking American identities in intelligence reports, significant questions would be raised. As ambassador to the U.N., Power, a long-time Obama adviser, held a diplomatic position. She was not an intelligence analyst. It is not immediately clear why the U.N. ambassador would be involved in the disclosure of American identities in intelligence reports — after the agencies that collected and analyzed the intelligence had decided such identities should be masked.

The Journal report further indicates that committee subpoenas demand any information related to unmasking requests by Susan Rice and John Brennan. Ms. Rice was President Obama’s national-security adviser (a White House staff position), and, as we’ve noted, previous reporting has tied her to unmasking activities. Brennan was Obama’s director of the Central Intelligence Agency. The CIA is in the business of gathering and analyzing foreign intelligence outside the United States. In that capacity, the CIA routinely makes judgments about whether identities of Americans should be unmasked.