US president-elect Donald Trump has taken only two classified intelligence briefings since winning the election earlier this month.  That is considerably fewer than his modern predecessors.

The intelligence community has a team of analysts preparing daily briefings on global developments and potential threats to the US and its allies in the two and a half weeks since the election.  By contrast, vice president-elect Mike Pence has reserved time every day to attend the briefing.

The transition team says Trump is busy interviewing candidates for his cabinet, which will include sensitive intelligence and security positions.  But there is unease in Washington and intelligence circles about a disengaged president-elect who appears more interested in parading potential cabinet members reality TV-style than in filling the gaps in his knowledge of national security issues.

"Trump has a lot of catching up to do," said a senior US official to the Washington Post.

The Presidential Daily Brief (PDB) is a summary prepared by the 16 US intelligence agencies to update the president and his top advisers and cabinet members on covert operations as well as key security developments and insights.  On 6 August 2001, then-President George Bush infamously took his PDB with a grain salt, and condescendingly told his CIA briefer, "Okay, you've covered you ass now."  That PDB was titled "Bin Laden Determined To Strike US"; 36 days later, the 9/11 attacks would claim 2,977 lives plus 19 hijackers.