The strength of the left has been its ability to tear itself to pieces more effectively than the right could ever do. This is seen all across the world, not just in New Zealand. I think acceptance of sometimes quite divergent opinion within a unified party is what we need to sort out before we can hope to take the fight to the right. In Britain in the 80s, Thatcherism triumphed because the left was split between Labour and the SDP. Because it was a FPTP system, Thatcher was able to win massive majorities on a declining share of the vote.
Obviously, things are a bit better under MMP, but I disagree with the suggestion that the fragmented nature of the left is not really a problem. If nothing else, it makes welding a coalition together more fraught; it also creates the problem of ideological dilution - there are some elements (and voters) of NZ First that are natural left territory, but the party itself is tainted with right wing madness and special interest pleading as to make it toxic; and there is the issue of perception - even if the dog is not being wagged by multiple tails - that the minor parties are getting undue influence and issue of stability will always be a factor for some voters; and the risk of unwise connections, as exampled by the recent dalliance of Mana and the Internet Party.
So I feel very disappointed when I see people continuing to rave about the supposed malign influence of Mallard-Goff-King, because a) I don't actually believe it, b) these are some of our most effective and recognisable performers, and c) it shows we still haven't learned the lesson and learned to accept the idea that people will have somewhat different ideas of what it means to be Labour, or the best ways to achieve leftwing goals.
This isn't to say the fault is the minor parties on the left; Mana is looking to Dotcom because it has been systematically excluded by Labour. and the Greens were blocked from coalition throughout the Clark years. To win, Labour needs to accept all strains of reasonable and sane leftism, and all strains of reasonable and sane leftism should be looking to form links with the larger party. Perhaps formal unification is impossible - but more co-operation and development of joint policy is essential. This means Middle New Zealand has to accept that Mana and the Greens are not swivel eyed eco-warriors and racial agitators; and the left needs to accept that Middle New Zealand is also part of Labour.