Ronald Kessler is a former Post reporter and the author of “The First Family Detail: Secret Service Agents Reveal the Hidden Lives of the Presidents.”

When Michaele and Tareq Salahi crashed a White House state dinner five years ago, President Obama said he “could not have more confidence” in the Secret Service.

When the Secret Service sent home 11 agents from Cartagena, Colombia, for hiring prostitutes, the White House said Obama had “full confidence” in the Secret Service.

When an armed intruder penetrated the White House itself in September, a spokesman again said Obama had “full confidence” in the Secret Service.

Even now, after two senior Secret Service managers suspected of having been drinking drove their vehicle, overhead lights flashing, through security tape at the White House and hit a temporary barricade, the White House said Obama has “full confidence” in his newly appointed director, Joseph P. Clancy.

Obama is in denial about the systemic problems at the Secret Service. In choosing Clancy in February to reform the agency, Obama ignored the chief recommendation of his own four-person panel that he name an outsider for the job. Instead, Obama turned to Clancy, a career agent who earned his trust as head of the president’s protective detail and who had been acting director since October.

Coming from the same culture that has led to all the failings, Clancy represents everything that is wrong with the agency. If there had been any doubt about that in Obama’s mind, it should have been dispelled when Clancy stonewalled at a House Judiciary Committee hearing when asked whether anyone would be held accountable for making false statements about Omar J. Gonzalez’s intrusion at the White House.

Even though the Secret Service knew immediately that Gonzalez had penetrated the White House and was armed with a knife, Clancy insisted that the agency did not intentionally issue falsehoods when it told the press that Gonzalez had been stopped at the door and was unarmed. When asked how he knew the untruths were not intentional, Clancy admitted he did not know how or why the false statements were made.

To Secret Service agents, Clancy’s appointment meant it would be business as usual at the agency charged with protecting the president’s life.

“Clancy staying is the worst thing that could happen to us,” a current Secret Service agent who did not want to be named for fear of retaliation told me. “He is cut from the same cloth as the previous recent directors. You have to get rid of that mentality. Agents will not speak out about problems because of the repercussions. He has made no effort to change that and will not make the changes that are necessary.”

As if to prove the point that Clancy was the wrong man to fix the Secret Service, in the latest incident, two weeks after Obama named him director, a senior Secret Service supervisor and another agent who was second in command of Obama’s protective detail plowed their cruiser into a security barricade at the White House. They were returning from a retirement party at a bar in Chinatown.

Officials with knowledge of the incident have told The Post that uniformed Secret Service officers wanted to arrest them and administer sobriety tests but were overruled by a supervisor, who let the agents go home.

Clancy’s response? He has moved the two agents into “non-supervisory, non-operational” jobs while an investigation is carried out, and he took no action against the supervisor. In contrast, when lower-ranking agents engaged prostitutes in Colombia, the agency put them on administrative leave and ordered them to turn over their guns, badges and credentials.

Equally revealing, it took five days for Secret Service officials to inform Clancy of the incident. That tells you everything Obama should need to know about whether Clancy has turned around the agency. In fact, since becoming acting director in October, Clancy has done nothing to change the culture of the agency, which punishes agents for reporting problems or threats and rewards with promotions those agents who ignore problems and pretend the service is invincible. As an example of that culture, a Secret Service uniformed officer who reported hearing gunshots fired at the White House on Nov. 11, 2011, but was ordered by her supervisor to forget it because he thought the noise was from a construction site, said she feared her bosses would criticize her if she continued to press the point.

With much fanfare in the press, Clancy pushed out several top officials who fostered a culture leading to laxness, corner-cutting and coverups. But unreported in the press, Clancy replaced them with managers who came from that same culture: Clancy has been rearranging the chairs on the Titanic.

Unfortunately, the one person who could initiate the needed steps to reform the agency by appointing an outside director who is immune from the corrupt management culture and is not beholden to interests within the agency continues to have “full confidence” in its operations — despite all evidence to the contrary. That is a dangerous delusion. It’s time for Obama to wake up and appoint an outsider such as a former high-ranking FBI official to end the decline of the once elite Secret Service.