not all refugees will be peaceful good people. within any group they are the majority are but you will find those who commit crimes, those who are violent, those who are rapists and we know some have come over and have connections with ISIS. do we only accept those who are nice people ? that is not what accepting refugees into a country is about and it is impossible to do
So in the aims of "being nice", we should accept refugees that may be members of ISIS? On what grounds does "being nice" override security and defence concerns?
I am sorry, but your statement seems misguided. The primary purpose of a State is to defend its own realm and its own borders because they are the parameters of its authority and power: they constitute the very nature of the embodiment of the State itself because they define its jurisdiction.
No state is under any obligation to admit anyone into its territory apart from its own citizens or subjects. The state can choose to be party to treaties or can pass laws that create such obligations; but in the same vein, it can also choose to revoke them. And, certainly, no state is obliged to admit foreign nationals, whatever their status, that it deems unfit.
If we pass legislation or policy that we will accept any refugee from a war zone, regardless of their background, history, or criminal record, then we have no grounds to prevent giving asylum to those involved in a conflict or whose presence in Britain may be detrimental.
Britain already has had fairly serious diplomatic issues with some countries over stupidly offering asylum to wanted criminals, terrorists, war-lords and people responsible for genocide. There is, at least, one mass murderer living in London, responsible for the deaths of thousands of Africans during a civil conflict.
In short: there is no "what accepting refugees is about" apart from what is enshrined in British law and the treaties that Britain is party to.