How to win broad support for green taxes
Three word answer: cut other taxes.
Traditionally, Green parties sit on the left of the political spectrum. But environmentalism, in its broader sense, enjoys genuine public support across political boundaries. Care for the environment has deep roots in conservative political traditions, both religious (Genesis 2:15) and secular (Teddy Roosevelt creating National Parks). You don't need to be a socialist to recognise that global warming is one of the major global challenges and that cutting carbon emissions would be a good idea.
One of the popular mechanisms for doing this is green taxes. Either the more complex (and market based) cap-and-trade type carbon tax or, more commonly, simply taxing high emissions activities such as petrol or air travel, to encourage people to use less of them.
The trouble is, this is normally presented as an extra tax. What's more, it's generally a tax that hits ordinary working people hard, not multi-millionaires. People on the right, in general, support lower taxes, because we believe ordinary people deserve to be able to spend their money as they choose, rather than have the government spend it for them (let's not debate this point now; hopefully we can all accept 'low taxes' is a pretty conventional right-wing view, regardless of whether we agree with it).
So even if we have sympathy for the aims of a new green tax - even if we agree cutting carbon is a national priority - to our eyes it looks a lot like another stealth tax to take hard working people's money and further increase already bloated public spending. What's worse, unless we're an expert in fiscal policy and behavioural science, it's very hard to tell the difference between a genuine behaviour-changing green tax and a conventional left-wing tax grab that's been labelled as 'green' to make it more popular.
So how to get broad-based support for green taxes? The simple answer is to cut other taxes - VAT or the base rate of income tax ideally, as these are the ones paid by most people. Instead of just proposing a new green tax, instead put forward a fiscally neutral package of swingeing tax increases on carbon-intensive activities and cuts to VAT and income tax, so that the overall government tax take stays the same over a five year period. This could be genuinely popular, as those who cut back on the carbon heavy activities would be genuinely better off.
Right and left may disagree about the optimum level of taxation. But if saving the planet is the primary goal they should be able to temporarily come together to shift the burden of taxation away from labour taxes on to carbon-intensive activities. For those whose priority is genuinely to cut carbon emissions, discard the temptation to use your carbon tax as a stealth increase in government spending, and instead win broad support for the change by making it fiscally neutral.