The UK has a long history of asserting rights of dominion over places and then abrogating its responsibilities.
Now that Iraq and Syria are coming under the heel of the newly emerging ISIS Caliphate, these people could argue that they have a fear of returning to where they came from, which would then mean they could stay in the UK as refugees with a real fear of persecution.
The UK allows 250,000 illegal immigrants to enter the UK each year using purchased NI numbers and bogus documentation to stay here and work. It allows rogue mosques including two in North London to allegedly preach sedition and treason, radicalize young men who then go abroad to commit murder and acts of terror and then return to a slap on the wrist.
Rightly the UK government should feel shame over its treatment of these unfortunates.