Maimane probably made a mistake too, but ultimately Zille needs to face a hearing (after all, other members have had to face hearings for similar stuff). And I'm not saying she has to clear every tweet with the DA top brass, but she really needs to think (and then think again. And maybe again after that) before she posts stuff.
As Johan points out, Twitter is a nasty medium and you can never make your intentions clear when using only 140 characters. So why on earth she thinks its a good idea to discuss colonialism in this medium, I have no idea. And everyt ime she posts rubbish like this, she takes the DA two steps back for every step forward - as a supporter, its very frustrating.
Oh, and I never said the party SHOULD take away her Twitter - I simply said they could solve half their problems by doing so!