U.S. citizens and residents who left their homes to join extremist groups fighting in Syria and Iraq appear to pose little immediate threat to the homeland, with only a handful even returning from the battlefront, according to a new study.

The multi-year effort by George Washington University’s Program on Extremism identified 64 so-called travelers who fought or otherwise supported Islamic State, al-Qaida and other groups in Syria and Iraq.

Of those, only 12 travelers are known to have returned, the study said. Nine of them have been arrested and charged with terror-related crimes.

And none have successfully carried out an attack in the United States, the study said.

The risk of returned travelers being engaged in terrorist attacks has, to date, been limited, according to the study’s authors.

There is currently no publicly available evidence to suggest that American travelers have slipped into the country without the knowledge of authorities, they wrote. ‘Homegrown’ extremists currently appear to be more likely to commit domestic jihadist attacks than returning travelers.

Compared to European countries, the risk such travelers pose to the United States, has always been smaller, partly due to the greater distance and difficulty in reaching the fight.

U.S. intelligence officials have estimated of the more than 40,000 foreign fighters who traveled to Syria and Iraq, only 5,000 to 6,000 came from Western countries.

The exact number who successfully left from the United States is unclear. Officials have said only that about 250 to 300 U.S.-based people left or tried to leave to join groups fighting in Syria. And not all of them made it.

The study found at least 50 � nearly one-third of all U.S. residents charged with Islamic State-related crimes � were arrested before leaving the United States.

Of the 64 travelers identified in the study who did manage to leave the U.S., 22 are thought to have died in Syria or Iraq. The whereabouts of another 28 are unconfirmed.

Attempted terror attacks

But in only one case did the study identify a returning traveler who sought to carry out an attack in the United States

That was 23-year-old Abdirahman Sheik Mohamud, a naturalized citizen from Somalia, who left his home in Ohio to join al-Qaida affiliate Jabhat al-Nusra in April 2014.

While in Syria, Mohamud was trained in explosives and hand-to-hand combat, and was then sent back to the United States in June to carry out an attack.

But in February 2015, while still in the early stages of planning, Mohamud was arrested. He eventually pleaded guilty and was sentenced to 22 years in prison.

Aside from Mohamud, only one other so-called traveler sought to carry out a terror attack, a suicide bombing, but it was only upon returning to Syria after evading prosecution in the United States.

In any case, the study authors say the data suggests fears once voiced by U.S. officials of a terrorist diaspora seem to be overblown.

Counterterror officials have admitted as much over the past several months, though they say even a trickle is reason to worry.

The quality of the fighters after the experience on the ground in Iraq and Syria is something we’re paying very close attention to, one U.S. counterterrorism official told VOA this past December.

Others have described them as force-multipliers, capable of having a disproportionate effect. And they worry, in particular, about the Islamic State terror group, which has proven especially adept at maintaining lines of communication even as its self-declared caliphate has collapsed.

So too, the George Washington University study finds there are reasons for concern.

While Mohamud was sentenced to more than two decades behind bars, study co-author Seamus Hughes says the average prison sentence for those who traveled to take part in the fight in Syria and Iraq is only 10 years, shorter than the average prison terms handed out to would-be U.S.-based jihadists who were arrested at the airport.

Part of that may be due to the difficulty in making a criminal case based on terrorist activity that took place overseas.

Hughes said another factor could be that the returnees may have been able to share intelligence or other information with investigators and counter-terror officials in exchange for lighter sentences.

But just like with the would-be jihadists, these travelers will eventually get out of prison. And Hughes and others worry the lack of deradicalization or disengagement programs could allow for problems in the future.

If left unaddressed, returnees can augment jihadist networks in the U.S., provide others with knowledge about how to travel and conduct attacks, and serve as nodes in future jihadist recruitment, the study warns.

Source: Voice of America