TLDR: terrorism only happens in the UK because Muslims. Apparently 30 years of IRA attacks didn't count as terrorism. And UDA, UVF and the whole alphabet soup of Catholic on Protestant, Protestant on Catholic hate, but it was the IRA that thrived on US support. And of course it's less than a year since Jo Cox MP was assassinated by a white racist, but of course that doesn't count.
The second comment reported would actually count as a hate crime if made in the UK.
The UK right-wing troll Katie Hopkins lost her job at a London radio station for similar comments (she called for 'a final solution) after the Manchester attack and has been reported to the police for them.
Meanwhile, there's a much better class of response reported here: J.K. Rowling is making important points after the London terror attacksETA: This one's too good to miss: Man Pictured Fleeing London Terror with Pint Still in Hand. As people are pointing out, given the price of beer in London...