Once upon a time, New Zealand was a nation with a proud environmental record, which took on the world and stood up for its green values, regardless of what the big countries wanted. We spoke out against nuclear testing in the South Pacific, for the creation of a South Pacific Whale Sanctuary, and against climate change. Now that proud record is in tatters, with the National government's public announcement that it supports the resumption of the commercial slaughter of whales.
This is being reported around the world. You can imagine what that is doing to the environmental reputation that underlies our tourism industry. But National doesn't care about that reputation. They think that "100% pure" is "unrealistic", not to mention a barrier to farming. So they've decided to trash it, with mining in national parks, fishing for endangered species, and now support for whaling.
The problem for National is that environmentalism is a fundamental part of our national identity. These moves strike at the heart of who we are as a nation (as does their new foreign policy of toadying to anyone who might give them an FTA at some unspecified time in the future). That's the sort of thing which causes governments to become oppositions. And the sooner it happens to this pack of spiteful orcs, the better.