Why is British nationality and culture suppressed or denied?

Why is the British nation state under what i would call attack.?? In schools now kids are not taught British history, why is this it is their country, a country with a rich history for good and bad....is it any wonder kids now have more in common with hip hop and islamic culture than anything British...fair play to kids from other cultural backgrounds and religious ideologeis as well as races...But they are now here in Britain and all kids in Britian should be taught about the greatness of Britains past , alongside the bad points too.....its only right....dont let these liberal cultural deniasts tell them otherwise.........is it any wonder Britain is fast losing its identity....