Of all the smart things said in our nation’s history, few are more true than FDR’s most famous quote:

The only thing we have to fear is fear itself.

There are entire industries devoted to exploiting fear in this country. If you can be convinced that something or someone is going to harm you in some way, you’re more likely to buy a product that you’re told will keep you safe. That’s why so many Americans own guns — and bought more when they were told “Obama is going to take your guns away,” all evidence to the contrary.

Fear is the reason we forsake our Fourth Amendment rights and put up with security theater at airports. It’s why the pharmaceutical industry tells you to “ask your doctor” about medication for conditions you didn’t even know you could contract. It’s why home security companies continue to thrive.

Next time you fly, browse through the SkyMall catalog and be amazed at how many items are offered that will supposedly make you more secure, from a keychain breathalyzer (because you should be afraid of your own drinking and driving) to a lung exerciser (you’re not going to let your lungs get all flabby, are you?) to a clip you wear around your neck to hold a napkin in front of your shirt to make sure it doesn’t get dirty (note to guys: chicks dig that look) to a covert alarm clock camera (so you can watch the people breaking into your house when you’re not there and re-setting your alarm to go off at 6pm instead of 6am).

Fear-based claims are often irrational, but not always. When your parents taught you to look both ways before crossing the street, you learned how not to get run over by a bus. Your computer password should be slightly more complex than “123456.” Teenagers shouldn’t rent a cabin in the woods next door to the guy in a hockey mask with a chainsaw.

Fear is also a factor in political beliefs, according to a new study published in the American Journal of Political Science, which begins:

Fear is a pervasive aspect of political life and is often explored as a transient emotional state manipulated by events or exploited by elites for political purposes.

It explains how fear can play a role in influencing political attitudes on hot-button issues like immigration and how individuals who are genetically predisposed to fear tend to have more conservative opinions, which play out politically as support for policies like anti-immigration and segregation. The researcher, Brown University professor Rose McDermott, says:

It’s not that conservative people are more fearful, it’s that fearful people are more conservative.

That’s why there’s so much fear-based right-wing media in this country. If you listen to Limbaugh, Hannity, Beck, or Fox News, you constantly hear about how some liberal politician or a group is coming to get you, hurt your kids, take your stuff. They are experts at exploiting emotions and exacerbating paranoia, usually over stories that have no bearing on most people’s lives, such as convincing viewers that two supposedly-menacing black guys standing outside a polling station represented a dangerous threat by the nonexistent New Black Panther Party. The whole “redistribution” argument is to convince paranoid white people that the government is going to take more of their money and give it to minorities. Fear mongering is why a Muslim community center several blocks away from the former site of the World Trade Center was turned into ginned-up rage over a “Ground Zero Mosque.”

Exposure to those constant messages from right-wing blowhards becomes a self-fulfilling prophecy. They tell you that you can’t trust any other news sources, that they alone speak the truth, that the others (“the mainstream media”) are purposely keeping details about this plot or that conspiracy from you because of a secret agenda to destroy America.

There’s no denying these fear-mongers are good at what they do, but that’s not a positive for society at large. What they specialize in is no more to our mutual benefit than Wall Street’s greed was good for our financial meltdown, or a quack doctor is to our health, or this Congress is to progress.

On a larger scale, fear is why we went to war with Iraq over weapons of mass destruction that didn’t exist. And why we stopped building nuclear power plants after Three Mile Island despite decades without another accident in other existing plants. And why ill-informed parents aren’t having their children vaccinated.

If our ancestors hadn’t overcome their fears, they never would have crossed oceans to get here. Humans would never would have set foot on the moon. Your child would never have left home to go to school. You never would have quit one job to take another.

Being afraid is no way to go through life. It’s corrosive, an impediment to moving forward as a society. It’s no way to greet the future.

Get over it.