The 30-minute YouTube video was the centerpiece of a campaign that spread on Twitter beginning on Tuesday via hashtags such as #Kony2012 and #stopkony. By Thursday, the YouTube video had been viewed almost 40 million times, while Tweets about Kony had become the No. 1 trending topic worldwide on Twitter.

A host of celebrities, including George Clooney, Rihanna, Justin Bieber and Oprah, joined the virtual chorus of support for the cause.

The campaign was the work of Invisible Children, a San Diego-based non-profit headed by Jason Russell, a filmmaker who had traveled to northern Uganda. The group urged people to help make Kony "famous," and many high school and college students especially apparently related to a message focused on helping innocent children. The Lord's Resistance Army has been notorious for kidnapping children and forcing them to fight.

Russell narrates the video, which juxtaposes shots of his young son in Southern California with the plight of scarred Ugandan children. Over a stirring soundtrack, Russell urges viewers to call legislators and government officials to sustain the U.S. military presence in Uganda.

He also encourages viewers to purchase an Action Kit, which includes "Kony2012"-themed posters, stickers and bracelets fitted with "unique ID numbers" that buyers can distribute to their friends.

"Our goal is to change the conversation," Russell says. "We have printed hundreds of thousands of posters, stickers, yard signs and flyers that are, right now, today, being put up in major cities all over the world."

The campaign is supposed to culminate on April 20, when Russell urges supporters of the movement to "blanket every street, every city."

CONFLICT HAS SUBSIDED

But the video has been heavily criticized for promoting a misunderstanding of the situation - beginning with the fact that Kony is believed to have long since fled Uganda for South Sudan or the Central African Republic.

Though his army once numbered in the thousands and sowed fear across northern Uganda, he is now believed to have only a few hundred followers and much of the armed conflict in the area has subsided.

The State Department said on Thursday it appreciated the campaign's effort "to shine a light on the horrible atrocities of the LRA" and that American forces were "already very much involved in helping Uganda and the neighboring states to root out Kony."

But spokeswoman Victoria Nuland dismissed suggestions that the United States could take a more direct role in the fight against the LRA.

"I don't think anybody in the region favors that. What they have asked for is this logistical, technical training, support and that is what we are providing," Nuland said, adding that she was not aware of any increase in phone calls or other public pressure on the State Department following the release of the video.

Critics of the Invisible Children campaign also said the video oversimplified the situation, created the illusion that posting messages on social media could have a meaningful impact on a long-standing human rights crisis and ignored the efforts of people on the ground who truly understood the situation.

A similar type of celebrity-driven campaign to "Save Darfur" fell short of its goal of ending genocide in a strife-torn region of Sudan and drew similar criticism.

"It's not a new message but it's done very well in attracting a lot of attention very quickly," said Tom Cargill, assistant head of Africa program at Chatham House, a British-based think tank.

"Its aim is obviously to influence U.S. policy ahead of the (U.S. presidential) election but I'm not entirely sure it's going to do that. Even if they do put more resources into finding Kony, he's proved very adept at evading attempts at capture before."

Invisible Children also faced questions about its governance in light of financial statements that show a majority of its funds were used for travel and film production rather than charity work. Amid rising scrutiny this week, the non-profit published its financial statements and responses to criticisms.

Rebecca Lieb, a marketing analyst at Altimeter Group, said the campaign showed "the tremendous power of content marketing on the Web. Nobody could've afforded to buy 30 minutes of airtime to push this out there on radio or television."

MIXED REACTION IN UGANDA

The video has drawn mixed reactions from within Uganda, where many civilians distrust the military and government forces are often accused of committing the same atrocities as Kony's fighters.

Angelo Izama, a reporter at the Daily Monitor newspaper in Kampala, the Ugandan capital, said the video was misleading.

"It is problematic that these children wanted people to know that the war is still going on," Izama said. "It's not."

"You've got almost racialist construction embedded in there," said Izama. "It's young white people coming to Africa to save deserving but hapless children from a monster that was created."

Uganda's armed forces, which have been hunting the fugitive LRA leader for more than two decades, welcomed the film and its massive viewership, saying it would "help us to expose who Kony is."

"I wish that it had come earlier," Uganda Peoples Defence Force spokesman Lieutenant Colonel Felix Kulayigye told the BBC's "World Have Your Say" program.

He said the Ugandan military was confident that it would finally catch up with Kony, though he declined to predict when.

"When you are dealing with insurgents ... it is never advisable to give yourself a time frame," Kulayigye said.

He added he had last seen Kony in South Sudan's Western Equatoria state in 2007 when the LRA leader had attended abortive peace talks before disappearing again into the bush. He said Kony had appeared "confused" there but "behind that mask lay a man with a lot of brutality."

Kulayigye acknowledged the Ugandan military had only managed to drive Kony out of Ugandan territory after more than two decades of killings and kidnappings by the LRA.

"We should have stopped him, that's a failure certainly," he said.

(Additional reporting by Pascal Fletcher in Johannesburg and Andrew Quinn in Washington; editing by Jonathan Weber and Mohammad Zargham)

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