The orientalist usually brings the ayah/verse from Al-Baqarah, 191:
And kill them wherever you find them, and turn them out from where they have turned you out.
And accuses the muslims that they are killer and this is taught in the Koran.
The answer for their accuses is that, we must look at the previous ayah, Al-Baqarah, 190:
And fight in the way of Allah those who fight you, but transgress not the limits. Truly, Allah likes not the transgressors.
Then, it is a common sense for a human to fight for his honor, land, family, religion or any of his right, if they are being threatened.