It's a very sad sign of the times. Too many people with conflicting values & traditions, forced to live cheek-by-jowl. It's no wonder that tensions are mounting under such circumstances.
The really scary thing is: someone videoed one of the suspects explaining why he did what he did, and he sounded quite rational. If his hands hadn't been drenched in an innocent man's blood, you might even have thought he was a nice guy. How can he sound so reasonable, and yet be capable of such an atrocity?
But scary as it seems, incidents like this are extremely rare, because you have to be a special kind of nutcase to do what those two men did yesterday. So please don't let it worry you too much. These kinds of nutcases have always existed (think of the Yorkshire Ripper, for example) but they are so few and far between that they tend to crop up once a decade, if that. And in a country of 70 million people, that means they're very rare indeed.
I don't know about you, Joey... but as for me, I'm wearing my 'Help for Heroes' wristband today and I will do every day until I no longer feel it is necessary to do so. I've also tried to make a donation but their website is down - which is excellent news because it means that we British have been so moved by what happened yesterday that we're inundating our main charity for helping wounded & disabled soldiers.
I will not be cowed by nutters. And neither should you.