Frazier Glenn Cross, the suspect charged with murder today in the killings of three people near Jewish sites in Kansas on Sunday, is a self-avowed anti-Semite who has founded white supremacist groups such as the White Patriot Party and a branch of the Ku Klux Klan.

Is this 73-year-old typical of today's Klan? With a sordid history and current climate of social intolerance for racism, why do people still join the Klan?

First of all, while there are nowhere near the millions of members the Klan attracted in the 1920s, tracking members of hate groups has become increasingly tricky. The central organization disbanded, bankrupt, in 1944. Many local chapters remained active, and other unaffiliated white supremacist groups formed. The Internet age further spurred the fragmentation, providing a forum for individuals to connect over long distances and fringe views.

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The Southern Poverty Law Center lists 939 active hate groups in the United States, but there's no way of calculating the total number of individuals involved in the groups. The SPLC estimates between 5,000 and 8,000 are members of various groups stating Klan affiliation. While most experts agree that the number is a very low percentage of Americans, they worry about violent outbursts like Frazier Glenn Cross's that don't require a broad, unified effort.

Photojournalist Anthony Karen has been photographing the Ku Klux Klan since 2005.

"Individuals affiliated with the Klan aren't part of an exclusive community -- a member could be your neighbor and you'd never know it unless they told you," he said. "I've documented Klan members in 14 states and one in Germany. I personally know members in states/countries that most would never think the Klan existed ... places like Vermont, North Dakota, New Jersey, Belgium, Italy, Spain and even Australia."

Indeed, the SPLC lists Klans in almost every state. For some, being a part of the organization has been a way of life since they were babies. Others seek it out, often as a way of rebelling for youth who feel marginalized by mainstream culture.

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"There are people who learned to hate from a very early age around the dinner table," said Jack Levin, co-director of The Brudnick Center on Violence and Conflict at Northeastern University who has studied hate crimes for 30 years. "And then there are so many teens and young adults who aren't making it and who want desperately to feel powerful and successful. They can't do it an any middle class sense of the word, so they gain a sense of dominance and control and power by assaulting vulnerable victims. And, they spend hour after hour on the Internet visiting hate websites, where they can not only get propaganda but also find like-minded individuals, whereas [before the Internet] they would have felt like loners."

At the peak of Klan membership in the '20s, many racist ideas were culturally acceptable and it wasn't uncommon for mainstream middle class people to join who "wanted to keep blacks in their place, but weren't out to lynch anyone." Today the group attracts more marginal types. The hate is more pathological than cultural, Levin said.

Frazier Glenn Miller is the former "grand dragon" of the Carolina Knights of the Ku Klux Klan, which he founded and ran in the 1980s.Southern Poverty Law Center photo

The Klan, meanwhile, has been distancing itself from the word "hate," perhaps in an effort to attract more middle class members -- or perhaps even in a more genuine sense, Karen said.

"I've met many people that claim they don't 'hate' anyone," Karen said. "They simply enjoy being in an exclusively white Christian organization, which supports ideals that the Klan champions -- such as a strong opposition of homosexuality, interracial relationships and advocating stauncher policy regarding illegal immigration. To others it's as simple as them wanting to be amongst similar minded people in a fraternal atmosphere."

But when individuals find a group like the Ku Klux Klan that validates their views, they're more likely to commit a violent act, Levin said -- even though those who do, like Glenn Cross, are the minority.

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"In my experience most current Klan related illegal activity has been at the hands of a random few, not an organized squad representing an entire organization," Karen said.

Like Glenn Cross, it has also become common today for members of such groups to jump from organization to organization, complicating the task of rooting out potentially violent characters.

"Just a few years ago, the National Alliance in West Virginia was the most dangerous group in the U.S.," Levin said. "Now, you can't find them."

As recently as the 1990s, the FBI could keep track of potential threats by infiltrating major groups, Levin said. Tracking down a lone wolf who may hop from group to group is much harder.

"Nowadays, it's almost impossible," Levin said.