I think this tragic incident will sadly repeat itself at some point in the future as certain sections of society tie themselves up in knots in trying to poorly balance the rights of those to profess their beliefs/views versus upholding British Values in the background of trying to avoid being called an Islamophobe/xenophobe/racist.
Equally, there are problems in how the British dealt with immigration ever since the Empire Windrush last dropped off migrants. We didn't help to integrate, mainly castigate, jeer and abuse certain minorities as they appeared different and as such, those minorities stuck together in communities that can generally be synonymous with whole towns and suburbs (Tottenham, Burnley, Dewsbury, Broughton) Nowadays, bad characters in all backgrounds can hide within their own areas easily as it is hidden in plain sight.
The third factor is those who wish us harm themselves. They see Western policy as generally Satan's to-do list. We cosy upto the likes of Saudi Arabia because without them, we have no oil which allows disturbing views on the world to filter in and sadly confuse some Islamic youth. Our politicians' failure to work together much better on combining a strong military strategy with a collaborative diplomatic policy has stymied and held back countries such as Iraq, Syria, Yemen, Somalia and Israel in turn bringing massive feelings of resentment towards the West who they see as being rich, naive, destructive and simply hating Islam.
I hope heads can be banged together but I think it will be an uphill struggle, especially considering no-one wants to sanction Saudi Arabia for fearing of losing all their oil.