Testimony from the nation’s intelligence director that Libyan dictator Moammar Gaddafi will “prevail” in that country’s conflict prompted an attempt by the White House on Thursday to play down that assessment and a call by at least one key senator for the resignation of the nation’s top spy.

The fallout was the latest example of the extreme sensitivity surrounding public comments by U.S. intelligence officials on events unfolding in North Africa and the Middle East.

The reaction to the remarks by James R. Clapper Jr. also reflects one of the precarious aspects of his job. As director of national intelligence, Clapper is expected to provide blunt assessments that aren’t shaped by politics, even though such assessments often create political consequences of their own.

Clapper stepped into Thursday’s controversy when he was asked to address the conflict in Libya. Gaddafi “appears to be hunkering down for the duration,” the intelligence director said at a Senate Armed Services Committee hearing, adding moments later that because the dictator has superior military resources “over the long term . . . the regime will prevail.”

Clapper’s testimony came after President Obama declared that Gaddafi no longer had a legitimate hold on power, and as the administration said Secretary of State Hillary Rodham Clinton would meet with leaders of the Libyan opposition.

Within hours, the White House was all but dismissing Clapper’s remarks. National security adviser Thomas E. Donilon described Clapper’s appraisal as “a static and one-dimensional assessment,” reflecting the lopsided division of military assets in Libya but not other forces sweeping through the region.

Sen. Lindsey O. Graham (R-S.C.) issued a statement calling for Obama to fire Clapper. The director’s comments “will make the situation more difficult for those opposing Gaddafi,” Graham said. “It also undercuts our national efforts to bring about the desired result of Libya moving from dictator to democracy.”

Pointing out that previous Clapper statements have also created controversy, the senator said the comments about Libya “should be the final straw.”

Clapper often serves as Obama’s primary briefer and is the intelligence community’s main voice on Capitol Hill. He has held the job since last August, and has been faulted for a series of public missteps.

Last month, his office was forced to issue a clarification after he erroneously characterized Egypt’s Muslim Brotherhood as a “largely secular” group.

In a December television interview designed to calm public fears about holiday terrorist threats, Clapper had to acknowledge that he was unaware of a bombing in London that had been the focus of abundant news reports that day.

He also raised eyebrows with other remarks in Thursday’s hearing before the Senate panel, saying at one point that China and Russia each pose a “mortal threat” to the United States.

Sen. Carl M. Levin (D-Mich.), the chairman of the committee, expressed disbelief at the comment, prompting Clapper to clarify that he was referring to the capacity of China and Russia to threaten the United States with their nuclear arsenals, not their intent.

Clapper is not the only top intelligence official to come under criticism for public testimony about the crisis in the Arab world. CIA Director Leon E. Panetta testified last month that Egyptian President Hosni Mubarak was expected to step down on the same day that Mubarak defiantly insisted he would remain in power. Mubarak did yield his position the next day.

In some ways, the criticism aimed at Clapper had more to do with the setting and timing of his comments than with their accuracy.

Lt. Gen. Ronald L. Burgess Jr., the head of the Defense Intelligence Agency, said he agrees that Libya has a military advantage and that “the initiative” in the conflict “may actually be on the regime side.”

Graham, who did not attend Thursday’s hearing even though he is a member of the committee, acknowledged that Clapper’s analysis “could prove to be accurate, but it should not have been made in such a public forum.”

When asked whether Obama is happy with an intelligence chief who “conducts static and one-dimensional analysis,” Donilon replied: “The president is very happy with the performance of General Clapper and we work together every single day.”