The logic explained to swp new members, is that Socialists oppose the Banning of fascist parties partially out of self interest. Historically, laws designed for banning fascist parties, have always ended up being used against the left. Further, they explain to new members, partially self interest motivates opposition to any increase in state power, because any increase in state power will usually be used against the workers movement necessary, and revolutionary organizations. Rightly or wrongly, this is what they believe. And given that most people on here think the only interest of swp is the existence of swp, your statement "Cos they're not really bothered" seems illogical. Of course they are bothered about the possibility that the swp could be banned. And of course it concerns them that such powers would also be used against the wider labour movement. So why don't they enforce it?
I think partially you are correct. The REAL problem with the UAF, which rarely gets discussed on here, is that it isn't the ANL. What I mean by that, is that it isn't a mass rank and file organisation firmly rooted in the communities up and down the country. There isn't a counterbalance to the deadwood of the labour movement bureaucracy. If swp did impose too much, the bureaucracy would just walk, and there wouldn't be a united front. But more important than this, the SWP also believe 'the masses' to be reformist. In other words 'the masses' and a bureaucracy have politics to the right of swp, which need to be attracted to the united front. SW believe this will not be done by preempting the discussion and imposing a revolutionary perspective. To preempt the united front to a revolutionary perspective is seen as revolutionary sectarianism. And this is similar to the argument made in the socialist alliance. This is a recurring theme in the swp. This is why they are always going on about sectarianism. They genuinely believe that revolutionaries can not impose upon the reformist masses and bureaucracy a revolutionary perspective prior, that these arguments have to be won whilst in united action. 15 years this has been the stratergy, and it has failed in both anti-fascism and Politics/politics to build a mass rank and file organisation firmly rooted in the communities up and down the country, however much the SW revolutionaries have bent over backwards. Why? Because the swp is just want a small front, they can control, they can recruit from? Bollocks!