Based on the way this discussion is going, I want to remind everyone of something:
Even Liam Neeson knows what he did back then was very, very wrong. And it is because it was wrong, and because he is ashamed of it, that he was sharing it.
Of course he was being racist. Of course he was wrong to look to just hurt someone for hurting his friend. That is what he is trying to say, and it isn’t easy to admit that he fucked up, and got lucky that he didn’t get the chance to fuck it up even further.
Editing to add: I for one am applauding him now for talking about it, for having the courage to admit his regret. Compare this to how the governor of Virginia is having trouble admitting that he went in blackface, for example. We need to encourage people to talk about past fuck-ups, damn it!