Fear sold the National Security Agency’s phenomenally intrusive program of spying on everyone and everything, but fear doesn’t explain it.

A nation reeling from terrorist attacks, the thinking went, would excuse the NSA’s vast eavesdropping on Americans and non-Americans, even friendly heads of state.

The reason for doing so, however, probably lay in something more mundane, more like the all-night party outside our apartment window last weekend.

Young men and women stood on a patio facing the courtyard of our U-shaped apartment building. They drank, and they talked. They drank more, and their talking turned to shouting.

By 4 a.m., their shouting and chugging were out of control. Who was going to stop them? No neighbor would dare knock on a door to confront drunks.

This was self-centeredness run amok. It was complete unawareness of consequences, complete disregard for the rights of others. An essential freedom to act had become a license to violate.

Sound familiar?

It’s the same thing that we’re seeing in the NSA’s egregious violations of constitutional rights, diplomatic protocol, and common sense. A gaggle of bullies acquired the tools to spy — like party hosts buying cases of alcohol — and they enjoyed using them. They found ever-new uses for them. They shouted because they could shout, and who was going to stop them?

Now people are knocking on their door, demanding that they stop their drunken revelry, and they are outraged at being unmasked and at being held accountable.

Never mind what damage they do to the nation’s character by imposing a surveillance state. Never mind what damage they do to national security by offending allies. Never mind what damage they do to an Internet economy based on the free and secure flow of information.

Never mind the damage they do to the president, who now must either defend their clueless intrusions or admit, once again, to being a bystander in his own administration.

Never mind the spookiness of capturing every email exchange and every cell phone conversation and then sifting through the haystack for whatever could be useful now or later.

Hey, the booze is endless, no one will complain with any likelihood of impact. Knowing secrets is fun. The technology is a gas. Thousands of NSA employees now feel more important. Shouting at 4 a.m. in disregard for one’s neighbors is a power trip. Let’s do it!

Unfortunately, the NSA’s revelry is a dangerous version of a broader debauch. Consider the post-adolescents running Facebook and making billions by selling people’s privacy to advertisers. Consider the Googlers who themselves scan every email and Web search for data to sell marketers.

Consider the armada of predators who swim into view when a person gets overextended on debt, loses a job, falls behind on a mortgage or misses a tax payment. Why chase ambulances when you can hack around public records to find neighbors who are too weak to defend themselves?

Self-centeredness is nothing new, of course. It’s as old as Adam and Eve. But for a time, ideals of community and shared sacrifice seemed to hold self-centeredness in check. Many of us think our nation is still playing by ethical rules that restrained an essential selfishness. Not so. We are knee-deep in plundering the weak and shouting at 4 a.m.

The NSA certainly is a villain. But even worse, it’s a symptom of a larger sickness.

Tom Ehrich is a writer, church consultant and Episcopal priest based in New York. He is the author of Just Wondering, Jesus and founder of the Church Wellness Project. His website is morningwalkmedia.com. Follow Tom on Twitter @tomehrich.