Thou shalt not criticize thine own candidate in print is one of the cardinal rules of working on a political campaign. So what does it mean for Ben Carson that two of his advisers have recently criticized his grasp of foreign policy?

The New York Times spoke to several of Carson’s foreign-policy advisers this week in the wake of his recent public struggles on the matter. While they praised the former neurosurgeon’s intelligence, some also raised concerns about his grasp of international affairs.

According to adviser Duane R. Clarridge, “Nobody has been able to sit down with him and have him get one iota of intelligent information about the Middle East.”

Carson, who has never held a position in government but is currently one of the top contenders for the Republican presidential nomination, has relied upon a network of paid and unpaid consultants with ties to international intelligence to bolster his credentials—a network he once half-jokingly bragged were better than Barack Obama’s.

Clarridge, a former spy who was indicted on charges of lying during the Iran-Contra scandal and was eventually pardoned, currently runs his own private intelligence network, once described by the Times as “something of a cross between a Graham Greene novel and Mad Magazine’s ‘Spy vs. Spy.’” After volunteering his services to Carson two years ago, Clarridge has helped him prepare for presidential debates and television appearances with regular briefings:

But the briefings do not always seem to sink in, Mr. Clarridge acknowledged. After Mr. Carson struggled on “Fox News Sunday” to say whom he would call first to form a coalition against the Islamic State, Mr. Clarridge called [Armstrong] Williams, the candidate’s top adviser, in frustration. “We need to have a conference call once a week where his guys roll out the subjects they think will be out there, and we can make him smart,” Mr. Clarridge said he told Mr. Williams.