In the wake of the latest security breach at the White House, there’s been a rush to diagnose the failures that allowed Omar Gonzalez to scale the fence, run across the lawn and enter the front door. People have called for all sorts of cosmetic changes to the White House fences and the grounds. But the truth is, none of these things alone will prevent another security breach. The Secret Service’s problems are systemic and strategic.

Following the assassination attempt on Ronald Reagan in March 1981, the Secret Service adopted an acutely vigilant mindset. The leadership put in place new strict measures to increase intensity and proximity of security around the president. For example, no one would be allowed within sight of the president without first going through a security screening magnetometer. Also, they increased the use of tents to shield the president from view when he was getting in and out of his car. And a solid working relationship with the president’s staff was given a high priority. The Secret Service was brought into the staff’s plans earlier and had a stronger voice to emphasize security when planning the president’s movements.

That attitude held firm through the Clinton administration. But a few years into George W. Bush’s first term, as leadership changed and institutional memory of the Reagan assassination attempt faded, the intensity began to disintegrate.

The first sign of this came in 2003, when Bush became the first president in history to land on an aircraft carrier in a fixed-wing plane. The president’s entry by Navy jet provided a flashy visual opening to his “Mission Accomplished” speech. But it was a very dangerous maneuver and an unnecessary stunt made simply for the sake of becoming the lead story on the evening news. A person close to the agency told me that the Secret Service originally objected to the plan, but eventually relented, given an agent would be in the plane with Bush — even though, if something had gone wrong, the agent couldn’t have done anything.

Under Reagan, the Secret Service never would have permitted it. Former agents told me they would have fought the idea tooth and nail. They would have thrown their Commission book on the table, refused to take responsibility and resigned. Then again, Reagan, who had been shot, had a special sort of trust in his agents.

Another sign that the intensity of presidential security has gone awry came in December 2008, when Bush was meeting with the media in Baghdad, and a journalist threw a shoe at him. In the footage, the one visible agent is not looking at the media people. He is sitting in the front row looking at the president, and there are no other agents even close to the president.

In the White House, there is a constant battle between the Secret Service and the presidential staff: The staff want him visible and accessible to the public. If the Secret Service had their way, he would mostly be cocooned. I have no doubt the Secret Service would never put the president in danger willingly. But the agents who protected Bush and the agents who now protect Obama never went through the trauma of almost losing a president. Without the weight of that experience, the Secret Service has not been able to recapture that obsession for proximity and intensity.

You can see that when you compare the way events were planned for Reagan vs. Obama. When Reagan spoke, there was almost never anyone on the stage behind him. In case of a threat, the Secret Service wanted a clear exit to get the president out of the area. Agents were always within a few feet of him. But with Obama, the setup looks different. People stand behind him, smiling, while he speaks. Agents are much further away. In one extreme case, Obama’s speech at the Lincoln Memorial in August 2013, he is in the middle of the set, alone, exposed to the huge crowd in front of him, and there is no agent within 30 or 40 feet.

The comparison is much the same with rope lines. With Reagan, there was one agent right next to him, while staff agents were in front and behind, touching people, talking to them — “Let’s see your hands, please.” — working the president very tightly. With Obama, rope lines make for great photos and great access to the public, but there’s no intensity. It’s almost as if his protective detail has been told to stay out of the photos.

Those senior Reagan and Clinton agents I’ve spoken with are concerned that protocols they established during the Reagan years are gone. They watch events where the president is in public and uncovered, and that’s inconsistent with the tradition in the Secret Service of always being close enough to react to the president.

From that, they say, comes the Gonzalez incident.

It is unbelievable enough that there was no one between the fence and the front door. But the door being unlocked changes everything.

The answer is not to reinforce the White House fence with concrete and barbed wire, add a second perimeter fence, take pedestrians off the sidewalk, and put SWAT teams on the lawns. It might not be a bad idea to replace the current fence with one twice as high. But it would be wrong to turn the White House into San Quentin.

Anyway, Band Aids will not prevent the next attack.

The answer is to call in some of those former agents from the Reagan and Clinton years, and let them preach to this bunch the hard lessons learned when a president got shot. Lessons of proximity and intensity. And of paying close attention to even the minutest of details.

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