Why ? Frightened people are more easily manipulated - and can be persuaded to do things they would not otherwise consider; to support policies they don't really like; to buy things they will probably never need; and to contribute money they can ill afford to grotesque people and causes.
The "Cause du Jour" varies. Right now, it's the construction of an Islamic center that will include a mosque - that is "mere blocks away" from 9/11's "Ground Zero" ...AND (less publicized) opposition to the construction of mosques elsewhere in the USA, because...mosques are attended by Muslims !!
Oh no !! Say it isn't so !!
Next thing you know, we'll learn Christians are building churches that will be attended by (Dare I say it ?) Christians; and Jews will be building temples and (sob !) yeshivas, and Hindus will be doing all manner of things....( I can't go on !!!)
Before we were alerted to the Terrors of Religion - Oriented Construction, we heard about the (Shudder !) Death Panels, that were supposed to kill off our Seniors by denying them health care.
This was a lie. Those who promoted the notion knew it was a lie; and-when a limited healthcare reform program was approved anyway, they dropped the lie like a hot potato - but did not admit their duplicity to the public. (There are still some folks out there quivering with fear they are going to be rounded up and sent to medical death camps : a belief the Fear Mongers find useful.)
There are also those who - even prior to the 2008 Presidential elections - promoted the idea any Democrat who was elected would be "coming to seize our guns."
This notion was promoted relentlessly - quite often by gun shops,distributors, and those who make a living from the production, promotion, and sales of firearms and accessories - including ammunition.
This promotion was wildly successful : guns-normally sold at reasonable discount-began to sell for prices closer to " List". Ammunition was purchased at similarly inflated prices and "stockpiled" by gun owners. (They get mad if you call it "hoarding".) So much ammunition was purchased ,there was a shortage; and factories had to work overtime to meet this unprecedented demand.
To make matters worse, some folks actually began joining homegrown "militias",playing "poop and snoop" in the boonies,and trying to figure out if they could trigger a civil war without getting hurt-if the candidates they favored did not get elected.
There have always been Fear Mongers around - but, in the past , it usually took so long for their poison to spread ,the effects were mostly local , and could be countered in time.
In our TMI (Too Much Information) Age, the results of well-told-lies are quickly visible: control over an increased segment of the population by an ad hoc Ministry of Fear.
Is that what you want for our Nation ?
UPDATE: Incident in Texas - still in "breaking news" category:
Predictable result of fear mongering: those who become "true believers"...