urban manchester and algarve street art.....

at the moment i am reading a book by dave haslam ex hacienda dj about the rise of the pop cult city manchester.............. tracing peoples leisure pursuits from the 1850s to the present day.......it would appear to revolve around drinking and brawling at the weekend.....the coming of the industrial revolution.....low pay....bad conditions....slum living....back to backs....the chartists....corn laws...........gang mentality....hanging around on street corners....the monkey parade....lads and lasses dressed in their best....out walking and srutting their stuff....each gang had a particular mode of dress.........teddy boys....mods and rockers....nothings changed............the music halls...the brothels....the temperance movement....too no avail.........fast forward to the arrival of jazz...the cinema.......influences of the usa.........as haslam says you cant put an import control on ideas and attitudes.......manchester has always been a raucus city right from the start.....london had little influnce over what went on....the cotton trade came and declined .....the great depression....it didnt dampen the cities young on their saturday night out...a taste of honey....love on the dole.........what has this to do with the art of the street??????????.......this then is the backdrop to urban art........what then is the connection with the sunny algarve and its street art??????? the obvious is the images more often than not appear in run down communities....yes they do exist here in the sunny algarve.........abandoned of all hope.... the arts council of england was set up to challenge the influnces of the usa and others.......to late!!!!!!!!! i want to try and understand a little more of why.it so proliferate...from tags to illustrations in their broadest sense.........some humourous...some political  and some unplacabl;e.....many angry!!!!!