Among its conclusions is that Obama, a former state legislator and U.S. senator, too often governed more like a prime minister than a president. In a parliamentary system, a prime minister is elected by lawmakers and thus beholden to them in ways a president is not.

As a result, Washington veterans have been brought into the West Wing to emphasize an executive style of governing that aims to sidestep Congress more often. A central ambition of Obama’s presidency — to change the way Washington works — has effectively been discarded as a distraction in a time of hardening partisanship.

The White House postmortem also concluded that the administration suffered from a lack of focus in a year without an election. The 2012 campaign imposed discipline on the White House, providing a political filter to assess every new initiative. Obama wanted to know how his decisions would be explained to voters, a demand that vanished once the election was won.

As a result, senior advisers now say, the White House’s focus did not match its ambitions as 2013 began.