It's easy for a thread like this to be twisted and misinterpreted, and end up as an Islam-bashing. I doubt that was the intention of the OP and it certainly doesn't have to descend to that level.
To those who say that Islam is a peaceful religion, why is it that the religion is mis-represented by so many utterly inhuman examples, who choose to use their religion as an excuse to perpetrate their primitive beliefs and inhuman actions? Why can't they simply say that they resent what has been done to their country by the US/Britain/France etc, who raped their soil for years to obtain cheap oil whilst giving bugger-all back to the countries from whence it came? To some, that in itself would be sufficient reason to harbour deep resentment and hatred towards the West, yet they choose to wage their war on religious grounds. Why do they insist that Sharia law replace the existing laws of other countries? Why is it that those same ratbags want to live in a manner the rest of the world left behind over 500 years ago?
There are a couple of examples in this thread of previous regimes that perpetrated inhumane treatment of innocents on a large scale, such as Naziism and racial murders in the US southern states, both instances obviously of so called "Christian" societal behaviour. However, unlike those examples, which were basically restricted in their breadth, the problem that these scum represent to the world is that they want to spread their evil to all corners of the earth and you don't even need to be an infidel to suffer their attention. Look at the numbers of fellow Muslims they are killing.
These vermin need to be treated not as Islamic radicals, but as the rabid dogs they are. Religion should play no part in justifying their extermination. The fact that they want to conduct a religious jihad is their problem. The world will have to treat them as it would any other deadly disease.