People need to get over this stuff. All this guilt by association from years past. It reminds me of an episode of question time where a member of the panel was ripping into Nick Griffin about the scum he had shared a stage with, and how he couldn't be taken seriously for that reason. Griffin was like "You do realise you're sharing a stage with me tonight, right?"
I prefer to assess the politician they are now and what they stand for now, as opposed to what they did in the 70's and 80's in a totally different set of political parameters.
If you can't forgive Corbyn for comments regarding Hamas, can you forgive the Queen for entertaining Martin McGuinness?
Yes, since the circumstances are different. One is a politician choosing to support a group because they share the same beliefs. The other is a head of state carrying out a duty required of them by their office. Not even similar.
Also, there's a big difference between sharing a stage with someone and agreeing with them. So that's another false equivalence.
Also relevant is the fact that neither Corbyn nor Abbott have said that they were wrong. So it's not about what they did in the 70s and 80s (and 90s). It's about what they're doing
now. Do they have different goals? Or do they just have different methods of reaching them now that they've acquired political power? Abbott hasn't even said that her views have changed - her response was that she'd become an MP (i.e. acquired political power), not that her views had changed. Even if you do ignore what a politician said and did for most of their political career, changing their tactics isn't the same as changing their goals or their political position.
Even without their support for terrorism and the overthrown of the UK, I wouldn't vote for them. I wouldn't vote for sexism and racism. So I wouldn't vote for the current Labour party, which is deeply committed to sexism and racism.