A complete lie moses. It is talking about people who are openly at war with the muslim state. Read the next verses:
4:90
Quote:Except for those who take refuge with a people between yourselves and whom is a treaty or those who come to you, their hearts strained at [the prospect of] fighting you or fighting their own people. And if Allah had willed, He could have given them power over you, and they would have fought you. So if they remove themselves from you and do not fight you and offer you peace, then Allah has not made for you a cause [for fighting] against them.
4:91
Quote:You will find others who wish to obtain security from you and [to] obtain security from their people. Every time they are returned to [the influence of] disbelief, they fall back into it. So if they do not withdraw from you or offer you peace or restrain their hands, then seize them and kill them wherever you overtake them. And those - We have made for you against them a clear authorization.
in short: killing unbelievers who are not physically trying to destroy the muslim state is absolutely forbidden.
Quran 2:256 is absolutely clear: "there is no compulsion in religion".
Elsewhere the Quran gives guidance for how muslim should engage in debate against people who have rejected faith, and to, as a last resort, part company with them (if they are trying to lead them astray). How does this make sense if muslims are supposed to simply kill them?