They are two separate groups with almost identical goals: The elimination of western civilization as we know it. And that is NOT an exaggeration.
Marxism, which is the basis of communism, socialism and American "extreme liberalism" is a philosophy that tries to form a society, complete with a centralized government, that controls all the people according to their "ideals" of the "collective." The Collective means the people as a whole and is the direct opposite of the type of individualism that the US Constitution is designed to protect and serve.
Islam is a total-control-of-society philosophy that has religious, governmental and personal elements which, again, aims to control everyone as a group or collective as opposed to allowing individual choices in what god to worship or how they should choose their mate, etc.
Remember that in asian and arab culture there is a saying: "The enemy of my enemy is my friend." These two groups both aspire to the totalitarian takeover of the capitalist/judeo-christian west which basically means the USA and our good allies like Israel and Great Britain.
If they are successful in defeating America and the west then they will have to fight each other for ultimate control of the civilized world.
Sounds like a bad movie plot? That's the world that we live in. We are fully engaged in a war of words and ideas NOW so that we can hopefully prevent a hot shooting war.
Sorry for the long post but that's about as simple as I can make it. Others can probably explain it better and more clearly.
Thanks that was great. I know this is a spiritual battle it and as I said in an earlier post, the marxists seem so repressed and bland, and the Islamists the opposite.