Sen. Joe Lieberman (I-Conn.) is publicly airing his grievances with the White House for not describing terrorists as "Islamist extremists."

In a handful of recent documents, the administration has instead used the term "violent extremists."

Lieberman made public on Tuesday a series of letters with counterterrorism adviser John Brennan urging the administration to be more specific about terrorist ideology.

"Accurately identifying our enemies is critical to understanding their motivations, capabilities and tactics — and to countering them effectively and defeating them decisively," Lieberman wrote in an April 22 letter.

Brennan responded that not all terrorists are "Islamists," and that using the term could engender backlash in the Middle East.

"Labeling these groups collectively as 'Islamic extremists' or 'violent Islamic extremists' could, in fact, validate the perception that they are trying to create — that, even though the overwhelming majority of their victims are themselves Muslim, Islam somehow justifies their actions, and that by fighting them the United States is engaged in a war against Islam," Brennan argued.

Lieberman pointed out in response that he favors the term "Islamist" over "Islamic," in order "to define our enemy as a political ideology, very different from the religion Islam, which is certainly not our enemy."

Brennan was apparently unconvinced, so Lieberman took his argument to the pages of the Wall Street Journal.