Fear.

You could smell it all over the story of Trayvon Martin. Fear in the call that George Zimmerman, self-appointed neighborhood watchman, placed to the 911 dispatcher about a suspicious figure in his gated community “looking about.”

Fear in the phone conversation Trayvon had at the same time with his girlfriend, saying that there was a man following him and that he’d put his hoodie on.

Fear in the agonized pleas recorded in a neighbor’s 911 call as the two struggled.

Fear of the nameless, faceless menace of the You-Shouldn’t-Be-Here. It’s the fear that makes you appoint yourself neighborhood watchman in the first place, to make sure nothing Out Of Place shows up. Fear that what you don’t know will hurt you. Fear, followed by rage.

Trayvon Martin was 17 and looked younger. He was carrying iced tea and Skittles. He was unarmed. George Zimmerman must have been terrifying — larger, older, carrying a weapon. Instead, Zimmerman was, by his own account, terrified. He pursued, shot and killed Trayvon.

Fortunately for the fearful, Florida’s “Stand Your Ground” law has their interests at heart. To get away with murder, you need not prove that anyone intended you harm before you shot him. All you need prove is that you were very, very afraid. You need a real and reasonable fear that your life is in danger.

But so few fears are. We’re more frightened of public speaking than drowning, of spiders than driving. What the law says is that force is justified if someone “reasonably believes that such force is necessary to prevent imminent death or great bodily harm.” In a word — fear. If my fear is big enough, it can outweigh your life.

This law terrifies me. I don’t suppose I can shoot it?

To Zimmerman, the figure in the hoodie was a nameless, faceless menace. But he wasn’t. His name was Trayvon Martin, “Slimm” or “Tray” to his friends.

He wanted to be an engineer, the stories report. He was taking flying lessons. He got A’s and B’s and was majoring, said his teacher, in cheerfulness.

Tom Wolfe, more cynical than I, notes in “The Bonfire of the Vanities” that every kid who dies unjustly and too early retroactively transforms into an honor student with presidential aspirations. This is not quite fair to their memory either, but it is the debt we owe the dead.

Dead children, dead kids, often carry with them the burden of our outsize hopes. “He could have been president,” one commentator noted. He could have been an astronaut. Hope can cast shadows as massive and false as those cast by fear.

We don’t know what might have become of Trayvon. Every possibility ended with those frightened pleas and the gunshot.

We live in a terrified age. You can’t ride a bicycle without a helmet. You can’t knock on your neighbor’s door. You can’t go on the Internet and talk to strangers beause the People You Don’t Know are Bad and Dangerous.

Not as dangerous as you are. You stab and stab at the shadowy Beast and discover it is nothing but a scared boy running along the beach.

Nice people don’t have racism, these days. What they have is something else. Localized fear. Fear of the life outside the gates. You go here. We’ll go here. This is your street. This is my street. This is my school. This is your school. Stay where you don’t look Out Of Place to George Zimmerman, and you’ll be safe.

Maybe the world is worse than it used to be. Certainly the nameless, faceless menace of the Rapist, the Home Invader, the Terrorist, the Child Molester is more terrible and present than it ever was. But even in the first of these categories, the statistics belie the image. Most people know their attackers. But the Faceless Menace is easier to fear. The Unknown is so much more frightening.

“I was afraid of him,” you say. “I was entitled to shoot. You never know what might have happened if I hadn’t.”

If George Zimmerman hadn’t, there would be one more face in the hallways at Dr. Michael Krop High School. And after that, who knows.

Trayvon Martin wasn’t a saint or an allegory.

Neither was he a faceless menace.

On Trayvon’s Facebook wall, a friend lamented the end of their plans. Plans. Faceless menaces don’t make plans. He was an aggressively normal kid, a threateningly typical teen. Only fear made him swell to these proportions. Now he looms over us, shadow fueled by rage and sadness. He’s not going anywhere. George Zimmerman’s getting real threats now.

This is where the fear gets us, and it’s a horrible place.

The Justice Department is investigating the case, after weeks of cover-up and bungling and failure to press charges by local law enforcement. But the standards for prosecuting someone for hate crimes are some of the highest set by law. The standards for shooting someone? Fear is enough.