there are differen't types of islamic extremists, and based on their oppinion you can split them into a left and a right wing.
For me I think having them grouped according to their disposition or stand would make the situation way worse because there will innocent that will be caught in the crossfire of religion segregation, if only these people understand the true message of Qur'an then there will be no more problem. If only there is a presence of love for human race then maybe they will open their minds that they can't force their beliefs to others and that their way of preaching their religion is wrong. I know that religion is a very touchy and I myself is not that religious person so I am not that good with these subjects but it makes me interested in the way they practice.
Generally, the words "left and right " have one meaning in the USA, and another meaning across the broader world.
I'm of the opinion they do not well fit the variations of Islam and Islamic extremism.
left -> back down on your direct national interest in the hope for moral gain.