AOG - // Until the authorities are prepared to admit that mistakes were made when vast numbers of an alien culture was allowed into the country, there is always going to be mad persons such as this killer venting they anger towards those who are committing acts of terrorism. //
Firstly, I don't think that the government admitting mistakes regarding an 'alien culture' as you so delightfully refer to it, is going to change the attitudes of people like this individual.
Secondly, this man did not 'vent his anger' towards those who are committing acts of terrorism, he picked on a group of worshippers at a Mosque - unless of course you believe that being a Muslim makes you a terrorist by default, and therefore fair game for a revenge attack.
// Muslims could not get on with other religions in their own sub continent, that is why they were given a country of their own, even then they were further separated by the creation of Bangladesh. //
I seem to remember Irish Catholics and Protestants having similar antipathy towards each other, and backing up their attitude with terrorist attacks - or does that not count because they are native terrorists?