Most were shocked by the charred scene of Joe Stack's kamikaze attack on a Texas IRS office, but for an alarmingly growing number of Americans Stack is a hero.

The destruction of the IRS office in Austin, Texas, has made suicidal pilot Joe Stack a hero to right wing extremists in the "patriot" movement.

(Maxx Scholten/The Daily Texan/AP Photo)
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The Web was studded with praise for Stack almost immediately after his plane slammed into the Austin office complex Thursday morning. The
admiring salutes appearing on sites ranging from Facebook to the pages
of extremist groups reflect what experts say is an "explosive growth"
in the anti-government patriot movement.

"Extremist groups are already aligning behind [Joe Stack], beginning to talk about him as a hero," said Mark Potok, director of the Southern
Poverty Law Center which studies American militia and hate groups. "The
growth of those groups has been astounding."

Stack's suicide note, an angry rant against the IRS and the government which was posted online the morning of his death, got around 20 million hits before it was taken down at the request of the FBI,
according to Alex Melen, president and founder of T35, the network
service provider for the Web site where the note was posted.

Melen, 25, said within minutes of taking the note down, the company was "bombarded" with around 3,000 e-mails demanding Stack's words be reposted. Some of the e-mails contained personal threats
against Melen.

"What's funny is most people were pretty much praising him," Melen told ABC News.

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Bob Schulz, founder of the anti-government We the People Foundation, said that while he only advocates non-violent means of protest, he can understand Stack's motives and said it is a reflection of a movement
unlike any he's ever seen.

"There's a huge patriot movement," Schulz said. "I've been doing this kind of work for 30 years. Never have I seen the likes of what's going on now. It's delightful."

The anti-government movement gathered strength during the early 1990s, resulting in several high profile stand-offs with the FBI. Anti-government militias trained in the woods and prepared for a
confrontation with the U.S. The militia movement peaked in 1995 when
Timothy McVeigh and Terry Nichols bombed the Murrah Federal Building in
Oklahoma City, killing 168 people.

The anti-government movement became dormant until the mid-2000s. Potok said a militia and extreme anti-government movement, fueled initially by
anti-immigration sentiment, is back in a big way, especially since
President Obama took office.

According to an April 2009 report by the Department of Homeland Security, the current anti-government climate "parallels" what federal officials saw in the 1990s.

"Rightwing extremists have capitalized on the election of the first African American president, and are focusing their efforts to recruit new members, mobilize existing supporters, and broaden their
scope and appeal through propoganda, but they have not yet turned to
attack planning," the report said.

For many, Obama's election was a near perfect storm of disappointments, Potok said.

"The longer term thing goes back seven or eight years due to immigration," Potok said citing the surge of border patrol militias like the Minutemen. "But Obama's election, which is in a way related to
the non-white immigration issue, was representative proof that this
country is irreversibly changing demographically. Then the economy has
played a role and things have gotten worse and worse."

The result is what Potok referred to as a "broad-based, right-wing populist rebellion," generally short of violent extremism.