According to recent reporting from CNN, a CIA source has revealed current agency estimates regarding the approximate manpower strength of the number of foreign fighters in Syria, as well as the number of individuals assessed to be fighting under the Islamic State (IS/ISIS/ISIL) banner.

Agency estimates provided to CNN assess that there are “more than 15,000 foreign fighters, including 2,000 Westerners, [who] have gone to Syria…and come from more than 80 countries.”

This estimate, which pales in comparison to ISIS’ estimated strength of 20,000-31,500 fighters (across both Iraq and Syria), is of significant concern in the context of ongoing US operations and support in the region, as well as for the governments and security officials of the countries from which these foreign fighters are originating.

With ISIS working to maintain control over its self-proclaimed caliphate and associated territory, and with countless militant Islamist groups and factions continuing to engage in combat with Syrian and other forces in the Levant, the US and any associated anti-ISIS coalition members will be forced to engage in both short and long-term operations to ensure that the threat from radical extremists is sufficiently mitigated.

While the short-term threat ISIS poses to the Iraqi government and Kurdish population (among any other countless religious minorities or victims of ISIS brutality) is no doubt of great concern, the long-term threat posed by returning jihadist fighters to their homelands is also a force to be reckoned with.

As greater numbers of individuals are inspired, motivated, or drawn to join any number of jihadist, militant, or Islamist groups currently fighting in Syria and Iraq, there is a pressing issue that will become more and more apparent to the various eighty countries from which all the fighters are traveling.

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Given the significantly high levels of training, combat experience, and further radicalization that individuals who choose to actively participate in the current jihadi movements in Syria and Iraq receive, well coordinated efforts by foreign fighters’ originating governments in the areas of intelligence, security, and other government offices will be required to stem any local activity upon their return.

With this long-term threat becoming more apparent as further extremist propaganda is published through platforms such as social media networks, YouTube, and other global information exchange mechanisms, it becomes even more imperative that the recently unveiled US strategy against ISIS and any affiliated jihadist groups is effectively implemented sooner rather than later.

It must be noted however, that this strategy poses several problems of its own, as the Long War Journal recently identified regarding the extremely complex situation in Iraq:

Iraq is far more complex. The Shia-led Iraqi government is close to Iran. And the Iranian-supported Shia militias that targeted and killed US troops between 2004-2011 are prominent on the Iraqi battlefield. American airstrikes have already been used by Iranian-backed forces, including known terrorist organizations, as cover for their on-the-ground advances. But Iranian extremists are not a viable partner, as their actions only inflame tensions among the Sunni population, creating more allies for the Islamic State, which can then portray itself as the only defense against Iran’s aggression.

Fortunately, the Kurds and the Sunni Awakening forces are willing allies, but cooperating with these groups will cause other groups to extract a price from the US. The US will need to keep pressure on the Iraqi government to include them going forward. And a major effort is needed to boost America’s meager assistance to these natural allies inside Iraq.

These are complex relationships that the US will have to address in order to effectively reach a desired end state for President Obama’s new ISIS strategy, regardless of how much financial backing, air strikes, intelligence, or other support is thrown at the problem.

While this is a daunting task in both the short and long term for the US and any coalition partners, it must also be noted that ISIS has also stretched itself relatively thin in regards to the number of options it currently has for partnerships of its own.

Due to its extreme ideology and practices, ISIS has effectively embarked on a strategy that will no doubt prove almost equally as difficult to achieve as well.  While it actively fights “two governments…[ISIS] is also fighting Hezbollah, the Peshmerga, the PKK/YPG, Iraqi militias, the Awakening, Syrian tribes, the Free Syrian Army, the Al Nusrah Front, the Islamic Front, and other groups, and now the US military, [all] in an area the size of a large American state, with millions of people living there.”

With the US strategy gathering steam over the next few months, it remains to be seen how effective it will prove in achieving US objectives in such a complex environment.

Thanks for listening.

(Feature Image Courtesy: NY Daily News)