andrekish - apparently, Islam does not mean peace. It means submission, although both salaam (peace, cf. Hebrew shalom) and islam (submission) share the same Arabic 3 letter root (s-l-m).
why do both sides always keep killing civilians who get in their way? - the West makes some effort to minimise civilian casualties; radical Islamists deliberately target civilians.
The West is as guilty as the East - not quite. For the West to be equally bad as radical Islam it would have to behead suspected terrorists in prison, Guantanamo Bay, etc. and film it.