How would England Recover from a very violent ww3 guerrilla warfare?

As in like. How would england recover from a very bad attack by offenders. and i am not talking about normal attacks or riots im talking about offenders having RPG-7 and AK47 and molotovs and than M9's and knives Cars mounted with Machine guns and trucks being used as support for the offenders. Well you get the point. Is there a way that England would recover from this type of attack? and for anyone thinking i am going to do this are stupid. Of course i wont do this =/