[The_Reader_David]

I wonder whether the use of green in the sense of 'unripe' used metaphorically to mean inexperienced works in Arabic as well (meaning not the color, but the Arabic for unripe use to mean inexperienced). If so, the snakes (meaning us or someone else the jihadis regard as enemies) can be destroyed (even) by the inexperienced.

[Oorang]

That, too, is a plausible explanation. I had not though along those lines. Young "unripe" jihadis willing to die for their "cause". But, does "green" have the same interpretation in their language/culture as ours, i.e. green = unripe?

[penguino]

Many times at SweetIslam they have referred to us - Americans - as snakes, like in a recent post that says "North America, land of criminals, serpents of the world". I agree with your idea that green equals inexperience and that the snakes (us) could be destroyed by the green meaning by the young or inexperienced.

Reading the passage:

The snakes can be destroyed by the green. Not worth attack. Best to slaughter the american dogs in my homeland. Dog lappers are nothing.

says to me that the Americans in the United States can be destroyed by even inexperienced fighters. It's a better tactic for them to slaughter the professional American soldiers in Iraq. Taking care of the lapdogs sitting at home will be easy.