Tommy Robinson is the product of the relevant authorities refusing to deal with certain issues. When rape gangs in Telford, Rotherham, Newcastle etc., are all being ignored because the police and authorities fear being labelled a racist, and when those on the far-left refuse to even discuss the issue and call people who dare speak of it racist, it was almost inevitable that people like Robinson, and quite a few nationalist groups like the English Defence League and Britain First, would be the ones to address it. If you ask me, few far-right groups would have the power they do today if politicians decided that equality meant treating British Pakistanis like everyone else and actually brought them to justice sooner for breaking the law and raping people.
As an individual, I don't think Robinson is so much malicious in intent as he is extremely misguided and irrational. He left the EDL because of extremists rising up in the party, which could be taken as an attempt to remove any association from the far-right. But not only is he now part of Rebel Media, he is breaking the law in contempt of court and probably isn't thinking things through. He's also got a confrontational vibe about him that makes it sound like everything is about to turn ugly. I think the man raises a reasonable issue to be addressed, but to me he has come across as a bit misguided in his efforts to try and report on the issues and has been irrational in his contempt of court. I had little sympathies for him when he went to prison in such a case.
As for why he's treated as a martyr? Well, because he's been made into one plain and simple. As long as the moderate and left-wing politicians turn a blind eye to foreign communities committing certain malicious acts just because the fear of being labelled as racist matters more than actually bringing rapists and grooming gangs to justice, then the vacuum gets filled by the right-wing. This is why Donald Trump was so popular among some people, because he actually had the balls to talk about issues the mainstream left and centrist even dare touch upon. It's too bad then that it had to be him to be elected to deal with the issue rather than someone more reasoned and rational who is able to see this issue as it is and deal with it accordingly. The populist will address the issue, but they won't even think about proper ways to solve it (ie. Boris Johnson with Brexit).
Ultimately, Tommy Robinson has support because he's been addressing issues the politicians dare talk about, and when the extremists join in, they start radicalising people by exploiting the concern that nobody else addressed beforehand. Imagine if you had a problem and nobody cared about it, going as far as insulting you and making out like you're something that you're not? Then suddenly one man comes along and offers to help you, and you accept his help. Since nobody else wanted to help, you have no interest in trying to listen to them anymore because they didn't care until now, and then anyone with actual malicious intent can exploit you without you even knowing so long as this person listens to you. It's how Anakin Skywalker became Darth Vader! Because one malicious individual did what nobody else would for him and offered to help him in his struggles.
Of course. Tom Robinson banned...
