Following the Islamic State's release of a video showing the beheading of abducted journalist James Wright Foley on Tuesday, many around the world have reacted with disgust, anger, and indignation.
In a statement earlier today, President Obama referred to the execution as "an act of violence that shocked the conscience of the entire world." US Secretary of State John Kerry described it as: "Ugly, savage, inexplicable, nihilistic, and valueless evil."
Twitter responded to the dissemination of gory stills from the video with the full removal of these images and the banning of certain accounts associated with the Islamic State (formerly known as ISIS). The hashtag #ISISBlackout also emerged as a way to protest the sharing of graphic pictures related to Foley's execution.
The video, entitled "A Message to America," has been deemed authentic by the White House's National Security Council. It features Foley delivering a statement regarding "his real killer," the US government. A masked figure stands alongside the kneeling journalist and speaks English, with a British accent, about recent US airstrikes in Iraq.
US President Barack Obama denounced the killing of journalist James Wright Foley in a press statement today.
Later in the video, another abducted American journalist, Steven Sotloff, is shown and threatened. The jihadist directly addresses the camera and says: "The life of this American citizen, Obama, depends on your next decision."
The US has now launched 84 airstrikes in Iraq since August 8, many around the Mosul Dam — which Iraqi troops and peshmerga fighters regained control of earlier this week.
"The video is designed to intimidate the United States, obviously, on the heels of US strikes against the Islamic State, but it's also to signal to the Islamic State's followers that no one will be spared in their conquest," William McCants, a Middle East policy fellow at the Brookings Institution, told VICE News.
British Prime Minister David Cameron, who returned to London early from vacation in order to address the situation in Iraq and Syria, said today: "We have not identified the individual responsible, but from what we have seen it looks increasingly likely that it is a British citizen."
UK officials have begun looking at videos of Guantanamo detainees and records of known British citizens in Iraq and Syria in order to find the suspect, according to the Washington Post. As many as 400 British citizens are known to have joined forces fighting in the region.
"We're absolutely aware that there are significant numbers of British nationals involved in terrible crimes, probably in the commission of atrocities," British Foreign Secretary Philip Hammond said on Tuesday. "Many of these people may seek at some point to return to the UK, and they would then pose a direct threat to our domestic security."
As many as 10,000 foreign fighters, 3,000 of them from Western countries, are believed to have joined the fighting in Syria, a counter-terrorism official told the Los Angeles Times last month.
"The US Administration has been warned about this and has thought about it a lot. It was one of the major issues that they were thinking about with regard to early intervention in Syria," Steven Weber, professor of political science at the University of California, Berkeley, told VICE News.
"If these things draw on for a long time, they become jihadi magnets, and that leads to more extremism, more radicalization, and managing the blow back from that is always an issue."
"It's something that the intelligence community spends an awful lot of time and resources trying to track," he said. "It's very, very hard to do, obviously."
Weber believes the Islamic State made a deliberate decision to use a fighter with a British accent in the video in order to send a message.
"I can just imagine, I don't mean to be glib in saying this, but a meeting of the communications team of ISIS saying, well let's put a guy with a British voice there just to show that we've got people who can do this, we can come at you in your home territory, you're not safe," he said.
"I think they probably underestimate the degree to which it just infuriates, and really can sort of turn up the emotional heat, and actually may have the exactly opposite reaction of what they want."
That anger was especially felt in President Obama's statement on Foley's execution today in which he said that the Islamic State "has no ideology of any value to human beings" and vowed that "we will be vigilant and we will be relentless."
However, it is not yet known exactly what that vigilance will look like. Earlier today, American officials told the Associated Press they were considering sending fewer than 300 troops to provide limited security in Baghdad, and airstrikes in Iraq have not been slowed since the video's release yesterday.
In this file footage, Foley, a graduate of the Medill School of Journalism in Chicago, speaks at the college during a 2011 visit. Foley spoke of his experience being held captive in a Libyan prison for six weeks. The discussion was held 15 days after his release.
But while strikes will likely continue in the region, it's unclear what can be done to avoid save Sotloff. He was abducted in Syria in August 2013 and it's unclear how he got into the hands of the Islamic State.
"You have to believe that the US was doing what it could to find where he was being held, but the fact the he was held for a year without US success in finding him means they're probably not going to find him before he meets a horrible end," said McCants.
The US has a longstanding policy of refusing to negotiate with terrorists. Foley freelanced for Global Post, among other outlets, and that news service stated today that they received an email threat to kill the journalist last week.
Global Post President Philip Balboni told NewsCenter 5: "We received an email from the captors on Wednesday night of last week stating their intention to execute Jim." Balboni added that the US government had been informed, but no negotiations were made.
So it's unlikely that a deal could be struck with Sotloff's captors, says Weber. "I don't think the United States is in any way interested in negotiating with these folks, so I think this is not gonna change anyone's policy in any way, shape, or form."
Follow Jordan Larson on Twitter: @jalarsonist