ISIS (Islamic State of Iraq & Syria)

[ShizGodsu]

The US might have highly trained troops but they would still be at a disadvantage in open conflict. Look at previous examples, Vietnam, Iraq and Afghanistan. It is very difficult to fight an enemy that blends in with civilians and that knows the landscape.
IS/ISIS/ISIL (or whatever they are called these days) are a big threat because of their rapid growth and their ability to attract vast amounts of recruits worldwide. They also have a good economic base by controlling oil fields and such so they can afford to continue operating and causing devastation.
They are also extremely brutal as shown by mass executions of their opponents and the shocking execution of that journalist Foley. The West however has got a difficult decision to make now because they are threatening to execute another journalist unless all airstrikes and such are stopped. Do they attempt to call their bluff or give into demands. I hate to say it but I feel the days are numbered for the other journalist.

The US took over Iraq in less than a month. That's the entire country. This shows how well trained and organized we can handle war against someone else. There are also other countries where we went in, filled the mission, and left in under four days.

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I beg to differ here. No special forces are better than the SAS. They are the best of the best.

SAS also joined US forces to hunt down ISIS militants. Some comparing the two doesn't do much since they're one temporarily.
Link.