WASHINGTON — Amid growing international outrage, the U.S. government has sent 30 military, intelligence and law enforcement advisers to Nigeria to help find 270 teenage girls kidnapped a month ago by Boko Haram, that nation’s most feared armed faction.

But in a nation where government is distrusted and politicians are resistant to accept help, how much the U.S. can do remains to be seen.

White House spokesman Jay Carney said Wednesday that the United States had deployed manned fixed-wing aircraft and drones in the search for the girls, who were taken from their school April 14.

Many think the girls are being hidden in small groups deep in Nigeria’s northeastern forests, in an area the size of New England, where spotting them will be difficult even with the best technology. And once they are spotted, military officials and experts agreed, the United States must be judicious in how it shares its intelligence with Nigerian officials.

Boko Haram’s grip on Nigeria, particularly in the northeast, where the girls were taken, is wide and thorough, running through every sector of government. A year ago Wednesday, Nigeria declared a state of emergency in three northeastern states, saying terrorists had created “fear among our citizens and a near-breakdown of law and order in parts of the country.” Since 2010, at least 300 students have been killed in attacks by Boko Haram, which loosely translates as “Western education is forbidden.”

The group has said it kidnapped the girls because they needed to be married off rather than schooled.

Yet until this case, the Nigerian government was reluctant to publicly pressure Boko Haram.

As one former defense official who worked on U.S. Africa Command issues explained: The U.S. “will have to be careful who it shares the intelligence with.” The official spoke only on the condition of anonymity, in order to talk freely.

Even if the girls are spotted, rescuing them poses its own challenges. On Tuesday, Sen. John McCain, R-Ariz., called for U.S. special forces to enter Nigeria if U.S. officials spot the abducted girls.

As it has done so in the past, Nigeria is unlikely to accept help, even on a case with this much international focus, and it would aggressively reject help were it to be forced on the country.

There also are domestic politics at play.

“My sense, always, on the political side was there was a fear that if they accepted help, the opposition would point and say, ‘See, this government is not capable of solving problems on their own,’ ” the former defense official said.