Attacks on the innocent – especially those in churches – may seem irrational and horrific to all but the attacker. But beneath the details can be a deep sense of victimization and scapegoating that may be tied to something as specific as hate based on race or sexual orientation or as broad as economic hard times.
"There's a whole category of mass killers who are seeking vengeance against a group of people who they feel are taking away their birthright, their opportunities, and making it difficult to succeed," says Northeastern University criminologist James Alan Fox, author of "Extreme Killing." "They don't see themselves as criminals, but ... as striking a measure of justice, winning one for the little guy. This case may show that [Jim Adkisson] perceived that society has been bending backward to favor disenfranchised groups so they're trying to get some justice for their own victimization."
Police say Mr. Adkisson, an unemployed mechanical engineer, left a note listing his own inability to find a job as one reasons for his attack. He also railed against the Unitarian Universalist denomination as being "liberal," including the church's advocacy for gay rights. The FBI is investigating the shooting as a hate crime.
"This is not just violence in a vacuum," says Brian Levin, professor of criminal justice and director of the Study of Hate and Extremism at California State University, San Bernardino. "When they perceive themselves to have played by the rules, they will lash out indiscriminately not just at innocent people, but innocent people who symbolize what they believe has done them wrong."
To be sure, any direct connection between the shootings and the nation's economic woes is hard to verify, says Cecil Greek, a criminologist at Florida State University in Tallahassee. More likely, Mr. Greek says, Adkisson's alleged outburst may have been tied into suddenly jarred expectations – in his case, his ability to find a job and even stay on food stamps – at a time when a majority of Americans are questioning the country's course and many are feeling an economic pinch.
"It's not as much if things are good or bad economically, but more whether people know what the limits are, and what they can expect," says Greek. "If it's a period where everybody downsizes, or a period of raised expectations where nobody knows where the upper limits are, it can be a more dangerous period to live through in terms of the potential for people to act out strangely."
The Appalachian South has seen economic change in recent decades, as jobs have moved overseas.
"For a male in American society, to lose one's job and to risk losing food stamps ... they have to find a plausible scapegoat," says Mr. Levin. "They will take that intense personal feeling of emasculation and failure and find some societal or political overlay that makes the failure seem not of their doing."
For churches, political violence has become a growing concern. There have been at least 13 major church shootings in the last decade, though the problem may be worse than that figure indicates, says John Casey, the former director of security at New Life Church in Colorado Springs, which was attacked by a gunman in December.
"All sin is irrational, so it's hard to know what's going through a person's mind," says Gary Cass, of the Christian Anti-Defamation Commission in Ft. Lauderdale, Fla. "It used to be that nobody would violate the sanctity of a church gathering, but that's no longer the case."
Still, while over 70 percent of serious church incidents involve domestic issues, such as child abduction or financial quarrels, the "avenger mentality" exhibited by Adkisson made his violence an unusual case.
"He saw this congregation not as a church but ... as part of the problem," says Mr. Casey. "He's thinking, 'I have to go there and do this to make the world a better place."
The church violence in Knoxville and elsewhere has jarred America's religious communities. Many congregations are already beefing up security, either employing security guards or trained parishioners with concealed-weapons permits. Some mega-churches, including New Life, have formed "intelligence" teams that keep tabs on unstable parishioners. "These [shooters] choose churches because they're soft targets," says John Nicoletti, a security expert in Denver.
But at a church targeted for its liberal views on sexuality and gender, officials said that cracking down on security would diminish the denomination's mission, especially in times of economic upheaval.
"There's an inherent risk in doing the work of religion," says Janet Hayes, a spokeswoman for the Unitarian Universalist Association in Boston. "There are practical steps that individual congregations can take to become more alert ... but you can't have a religion behind locked doors."